RCLT, Heavy Duty

The only Rock Crawling HD IFS + HD Steering Kit

RCLT HD Components, not including full hardware kit

RCLT HD One-piece Knuckle vs. Stock two-piece Knuckle

RCLT HD Lower Control Arm Detail, with 1/4" thick inner plating

RCLT HD Upper Control Arm Detail, with 1/4" thick inner plating

Typical bushing vs. Oversized RCLT HD bushing (33% more dampening)

3rd gen Tacoma on 40s (@SlowestTacoma), 4th gen 4Runner on 37s (@lostinthewoodst4r)

5th gen 4Runner on 37s, built by De Anza Auto Repair

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Qty:

Price:

$6,299.00

Base SKU: MCSU-181021

Vehicle*

Year*

Length*

+2.75 (5.50-inch width increase)

+3.50 (7.00-inch width increase)

Required Flat Rate Shipping (US Lower 48 States)*

Flat Rate Shipping, +$200.00

Pick-up product in person once ready

Attention all overlanding and off-road enthusiasts! Are you ready to take your Toyota Tacoma, 4Runner, FJ Cruiser, or Lexus GX to the next level? The Marlin Crawler RCLT HD kit is here to upgrade your front suspension and steering systems, transforming your vehicle into an off-road powerhouse. With more wheel travel, increased stability, better ground clearance, and maximum durability, you'll be able to conquer any terrain with confidence.

What sets RCLT HD apart from other long travel kits is its patented 2-inch forward geometry, replacement heavy duty & oversized knuckles (included), and integrated replacement steering rack (sold separately), providing the most durable and high-performing long travel IFS kit on the market by a wide margin. Made from high-strength USA-made materials and reinforced components, this kit can withstand even the toughest off-road conditions, including rock crawling and other challenging situations. You'll be able to take on larger obstacles and navigate rough terrain more easily than ever before, without worrying about damaging your steering or suspension.

Not only does RCLT HD improve your vehicle's off-road performance, but it also enhances your ride quality for both on- and off-road adventures. Designed to work with a variety of tire sizes up to 40-inch, you can customize your setup to fit your needs. Whether you're a seasoned off-roader or just starting out, the Marlin Crawler RCLT HD kit is the ultimate way to boost your vehicle's performance and elevate your adventures to new heights and reliability.

So what are you waiting for? Upgrade to the Marlin Crawler RCLT HD and experience the ultimate in off-road capability. With our patented design for enhanced approach angles, increased tire to body mount clearance, and perfect integration with the heavy duty MarRack steering rack, you'll be able to conquer any trail without fear of steering or suspension failure. Don't settle for average - take your off-road game to the next level with Marlin Crawler.

RCLT HD is protected by the following patents: 11066099, 11667327, and others pending.

Welcome to the BRAND NEW WORLD of Toyota IFS Off-roading

The facts are simple:

A 35" tire is the minimum entry size to be taken serious as a Rock Crawler
No Long Travel IFS Kit can Rock Crawl 35" tires without modifying the cab A-pillar mount, and therefore
No Long Travel IFS Kit is designed for Rock Crawling

The goals of the all-new Marlin Crawler Long Travel IFS:

To install 35" tires without cab mount frame bracket modification
To improve approach angle closer to or on par with Solid Axle Conversions
To take full advantage of the Heavy Duty MarRack Steering System
To carve a new path away from existing Long Travel kits not designed for Rock Crawling

How Marlin Crawler accomplished this:

By moving the knuckle forward for tire clearance & approach angles never done before
By increasing ground clearance of the traditional lower control arm design to a level never done before
By having the strongest factory-style steering system integrated with the IFS in a way never done before

What this means for you:

✓ The Ultimate Reliable HD IFS + Integrated HD Steering System Upgrade
✓ Maximum confidence for your Rock Crawling, Expedition, Overlanding, and Daily Driving needs
✓ Increased steering power to safely operate oversized tires
✓ All-new steering geometry properly designed for a lift (5" capable, 3-4" recommended)
✓ No need to trim, relocate, or chop body mounts (verified with up to 38" tires)
✓ No more broken inner or outer tie rods
✓ No more broken steering racks
✓ No more broken or bent knuckles
✓ No more broken axles (using Ultimate Build)

The Patented RCLT HD is born

Welcome to the birth of the Toyota Rock Crawling IFS industry, brought to you by the founder of the Rock Crawling industry, Marlin Crawler. RCLT HD stands for Rock Crawling Long Travel, Heavy Duty, and is the first Long Travel IFS Kit specifically designed for the Rock Crawler. With many unique & industry-first features, it has created a new market segment strong enough for Rock Crawling yet familar for all styles of use including overlanding, expedition, and daily driving. Main features include...

Relocate front axle so far forward it requires a new complete heavy-duty steering system,
Unmatched IFS steering strength,
Unmatched IFS knuckle strength,
Unmatched IFS geometry stability,
Unmatched IFS approach angle,
Unmatched IFS ground clearance,
Oversized bushings to absorb hits & loads,
Flex greater than wider kits reusing stock knuckles (2.75" kit achieves 14" hub travel, demonstration video),
Ability to run up to size 38" tires without body mount frame bracket modification, and
It is the first IFS system that challenges the benefits of a Solid Axle Swap

For these reasons, RCLT HD avoids competing with existing Long Travel kits and is why RCLT HD is proudly Patented!

Approach Angle, Ground Clearance, and Steering Strength are all serious handicaps to the IFS off-roader and RCLT HD greatly improves all three!

RCLT HD is 100% designed, developed, tested, manufactured, and built in Central California, using USA steel with USA-made FK bearings and tie rod ends. Comprised of 248 carefully designed individual parts, it is not just another Long Travel kit. This is a first-of-a-kind full IFS and steering systems integrated replacement consisting of...

Never-before-done two-inch forward control arm geometry,

Never-before-done knuckle geometry, and

Never-before-done steering geometry

...and made possible by the MarRack steering rack replacement and our extended length steering arms that reduce driver steering effort perfect for handling oversized tires on- or off-road. In fact, RCLT HD has the strongest Toyota Long Travel Knuckle ever made, with our signature one-piece steering-hub-caliper solid lower section cut from billet larger than two dual case adapters!

Strength, handling, steering, ride quality, & on/off-road
traction is unparalleled in the Toyota IFS market

Patented Heavy-duty Steering Integration replaces your original light-duty steering components

While RCLT HD was never meant to replace a Solid Axle Swap, it greatly challenges the benefits thereof in the following ways:

RCLT HD has vastly more ground clearance and less unsprung mass than an SAS
Is 99% bolt-on and easily transferable from vehicle to vehicle
May be removed and all original IFS components reinstalled
Retains all factory ABS, cruise, and traction control systems
Reuses OEM brakes and hub components for ease of service
Can be aligned by any shop without special instructions
Retains superior handling, ride quality, & stability for daily-drivers
Is less expensive and complicated to install

"I've wheel'd a lot of rigs and my Tacoma on 38" tires is the only
Rock Crawler I've ever built that drives like a Camry" — Nate, Dirt Lifestyle

Installation Overview

RCLT HD is a replacement Heavy Duty IFS with integrated Heavy Duty MarRack Steering System comprised of many patented features. This installation process is more time consuming than traditional Long Travel IFS installation due to (1) modifications required to install the oversized MarRack rack & pinion steering as well as (2) fitting factory knuckle components onto replacement Heavy Duty Knuckles.

The installation process is divided into four sections:

1. Power Steering System Flush
2. Remove Factory Components 3. HD Steering Installation
4. HD IFS Installation

Estimated Installation Time: 2 to 5 days

Please note this is ONLY to install RCLT HD. Your up-travel and tire choice will greatly impact how much extra labor is required to complete your desired build. The basic install is 35" tires with our included low profile bump stops, which requires minimal or no body trimming depending on application. To understand the scope of this product, please click here to view our detailed instructions. All orders receive exclusive access to our online installation database with 1-on-1 support.

Frequently Asked Questions

Bookmark link: MarlinCrawler.com/RCLTHD/FAQ

• Applications

• Specification

• Install Questions

• Body/Bumper Clearancing
• Bump Stop
• Coil over
• Coil Spring Rate • Inner Tie Rod (ITR)
• Steering Angle & Stop
• Suspension Travel
• Sway Bar • Toyota Safety Sense
• Traction Control
• Wheel Backspacing
• Wheel Diameter

• BigMike's Q&A to Dirt Lifestyle's RCLT HD Install Video

• What does "Long Travel" mean?
• When will it be available?
• What does it fit?
• What makes it different?
• What frame mods are required?
• What skills & equipment needed?
• How long to install?
• Any advantages over SAS?
• How does install compare to SAS?
• How does cost compare to SAS?
• Rear 3-link vs SAS?
• Why costs more than other kits?
• What is the MarRack?
• How strong is the MarRack?
• Can MarRack be used on other kits?
• Do we offer the MarRack? ^{UPDATED 11/21/23}
• Power steering upgrade required?
• Can other kits Rock Crawl?
• How strong is the IFS differential?
• Can it be used for High Speed?
• Fits foreign applications?
• Compatible with Big Brake Kits?
• How much travel does it make?
• Tacoma frame compatibility?
• Compatible with skid plates?
• How long do Uniballs last?
• Headlight relocation?
• Unfair jackstand comparison?
• Will Nate's Tacoma be at KOH?
• How was Nate's coffee?

• Type I, II, III, & IV IFS Frame Identification Chart

• Prototyping and Testing

Vehicle Application

2003-2015 Type III (Prado 120) IFS Platform (all 4WD)

2003-2009 Lexus GX470
2003-2009 Toyota 4Runner
2005-2015 Toyota Tacoma
2006-2009 Toyota FJ Cruiser
Any Right or Left-hand drive Prado 120-type global platform
- May require engine oil pan and/or mount modification

2010-2023 Type IV (Prado 150) IFS Platform (all 4WD)

2010-2023 Toyota 4Runner
2010-2014 Toyota FJ Cruiser, USDM
2010-2023 Toyota FJ Cruiser, Foreign market
2010-2023 Lexus GX460
2016-2023 Toyota Tacoma
Any Right or Left-hand drive Prado 150-type global platform
- May require engine oil pan and/or mount modification

Other applications

We receive requests for Type I, Type II, and 100/200-series LC applications. Because the 2003+ Toyota/Lexus mid-size platform is the most common, we began with Type III/IV. For Land Cruisers, sorry but there isn't enough demand.

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Specification

"+2 RC": Rock Crawling (RC) capability

Knuckle moved forward +2.00 inches (50.8mm)
Approach Angle comparable to a mild Solid Axle Swap setup
No body mount chop or relocation required with up to size 38" tires

"+2.75 LT": Extended control arms for Long Travel (LT) capability

+2.75 inches (69.85mm) longer per side, overall track width increase of +5.50 inches (177.8mm)
- Or +7 inches (139.7mm) wider overall for our +3.50 inch (88.9mm) kit
Improved side-hill stability, ride quality and smoothness over terrain
New Mid-length Solution:
- Between industry standard of 2 and 3.50" widths
- Maneuverability: Being too wide is often detrimental on technical trails (as well as city driving)
- Flex: Horizontal ball joints maximize articulation
  - +2.75" kit achieves up to 14.0" of travel at the hub, which is 12% more than typical +3.50" kits yet is 27% more narrow

"HD": Heavy Duty (HD) Boxed design
Including HD Knuckles and integrated HD MarRack Steering Rack

Maximum strength, durability, reliability, dependability
Double-sheer Horizontal Ball Joints top and bottom with 1-Ton ⁵⁄₈" LCA hardware
Double-sheer 1-Ton ⁵⁄₈" Tie Rod steering hardware
Extended height knuckle for reduced bump steer and rate of camber change
- Proper Knuckle geometry for lifted applications
- Maintains alignment for a greater range of motion than LT kits re-using stock knuckles
Better handling and ride quality compared to LT kits re-using stock knuckles

Put the three together and you get,

+2 RC +2.75 LT HD

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Install Questions

Body and/or Bumper Clearancing

RCLT HD repositions your front tires forward 2-inches which may cause cab, fender, and/or bumper interference depending on tire size and ride height. Bear in mind that because lifting an IFS is only practical up to about 4.5" or less, IFS builds are best suited for a low center of gravity and stability on sidehills/off-camber situations. As a result of the body remaining low, depending on your up-travel amount 35" tires may require fender clearancing and larger tires may also require clearancing to your inner fender wells depending on tire size & application (which may also involve repositioning of your main battery, windshield washer tank, and engine fuse box). The +3.50" kit will help reduce inner fender well trimming on more extreme builds.

Bump Stop

To maximize ground clearance, an RCLT LCA extends horizontally off the frame which constrains bump stop spacing. Using MCSU-761 Low Profile Bump Stop limits total hub travel to 11.6-inches. Taller bump stops, such as DuroBumps' DBF17T may be fitted to eliminate or reduce fender or cab trimming. Installing custom hydro bump stops will net the full articulation performance of the kit. As of Summer 2023, we now have doubled the bump stop landing area on the LCA for improved bump stop options and mounting versitility.
RCLT HD Owners: Click here to view custom bump stop examples.

Not designed to be jumped
Using factory bump stop brackets
Designed to be jumped
Using custom fabricated bump stops

Coil over

RCLT HD is designed for use with 2.5" diameter coil overs typically used on Long Travel setups. We recommend a 16.5" collapsed, 24.5" extended, and 8" stroke length shocks with 1.5" wide ¹⁄₂" lower mount hardware. Longer or shorter shocks may be used which may affect up- or down-travel.

Coil Spring Rate

Within the confinements of RCLT HD being a near bolt-on system, it is strong enough to handle anything thrown its way. Due to use preferences ranging from Rock Crawling, Baja, Sand, Mud, Snow, to Overlanding, as well as vehicle configurations from heavier 8cyl SUVs with full plate armor and coil rear suspension to lighter 4cyl single cabs with tube bumpers and leaf springs, there is no one-spring-rate-fits-all solution.

The answer to what spring rate is right for you depends on how your vehicle is configured and how you plan to use RCLT HD. You may find yourself tinkering with your spring rate to suit your needs. The goal for Rock Crawling would be to have the front and rear suspension complement one another, whereby the front spring rate is not too high that it causes the rear suspension to be over-worked. The following table as a general guideline suggestion:

Use case Empty Vehicle Weight Rear Suspension Suggested Spring Rate

Rock Crawling 4,500 lbs Coil
Leaf 500 lb-ft
500 or 550 lb-ft

4,500 to 5,250 lbs Coil
Leaf 550 lb-ft
550 or 600 lb-ft

5,250 to 6,000 lbs Coil
Leaf 600 lb-ft
600 lb-ft

6,000+ lbs Coil
Leaf 600 lb-ft
650 lb-ft

Baja / Sand 4,500 lbs any 550 lb-ft

4,500 to 5,500 lbs any 600 to 650 lb-ft

5,500+ lbs any 650 lb-ft

Use case	Empty Vehicle Weight	Rear Suspension	Suggested Spring Rate
Rock Crawling	4,500 lbs	Coil Leaf	500 lb-ft 500 or 550 lb-ft
4,500 to 5,250 lbs	Coil Leaf	550 lb-ft 550 or 600 lb-ft
5,250 to 6,000 lbs	Coil Leaf	600 lb-ft 600 lb-ft
6,000+ lbs	Coil Leaf	600 lb-ft 650 lb-ft
Baja / Sand	4,500 lbs	any	550 lb-ft
4,500 to 5,500 lbs	any	600 to 650 lb-ft
5,500+ lbs	any	650 lb-ft

Inner Tie Rod (ITR)

Because light duty steering rack tie rods are weak, clevis-style aftermarket upgrades have existed for a long time. RCLT HD features Heavy Duty oversized inner tie rods that thread into Heavy Duty DOM Marlinks which connect to Heavy Duty CNC billet knuckles using Heavy Duty ⁵⁄₈" 1-Ton double-sheer hardware. Our knuckles also feature longer-than-stock steering arms which reduces stress experienced up-stream on all steering components including TRE, ITR, steering rack and rack mounts. We have over 55,000 miles of testing 40" tires as well as 35" tires used in 3 x King of the Hammers & 2 x full Ultra4 Rock Racing seasons and have yet to experience any tie rod failures.

RCLT HD is now the remedy to this age-old problem and aftermarket tie rods are no longer needed. This is great because clevis inner tie rods are typically incompatible with tie rod boots which leads to seal contamination and premature rack failure. Therefore, we strongly appose using clevis-style inner tie rods with your MarRack. To maximize MarRack life, stick with its original factory-style inner tie rods which we have yet to see fail.

Steering Angle and Steering Stop

Our horizontal double-sheer knuckle connections trade maximum steering angle for maximum strength and suspension travel. We limit steering loss by using each uniball assembly as the steering stop, with staggered-width cups and high clearance misalignment spacers designed to interfer in unison. The result is 4 steering stops per side as opposed to the factory's one. Our steering stops must be broken-in before maximum turning angle is achieved.

Depending on usage, break-in may take a few trail runs to occur. To accelerate process, perform excessive sharp u-turns as well as sharp cornering while articulating the suspension. Below is a table of applications we've measured in comparison to RCLT HD.

Application Axle Type # of stops Steering Angle Full Sweep

RCLT HD, fresh install IFS (Type III or IV) 8 29° 58°

RCLT HD, broken-in IFS (Type III or IV) 8 32° 64°

1998 4WD 4Runner IFS, Stock (Type II) 2 30° 60°

2016 4WD 4Runner IFS, Stock (Type IV) 2 30° 60°

2021 4WD 4Runner IFS, Stock (Type IV) 2 29.5° 59°

2008 4WD Tacoma IFS, Stock (Type III) 2 36° 72°

Live Axle Comparison

Marlin's 1980 "Crawler Truck" 8" Toyota Axle with High Steer 4 28.5° 57°

BigMike's 1981 Pickup 8" Diamond Axle with High Steer 4 31° 62°

1985 4Runner FJ80 + Hellfire Knuckles, High Steer 4 30.5° 61°

1996 FJ80 Land Cruiser Land Cruiser, Stock 4 32° 64°

Application	Axle Type	# of stops	Steering Angle	Full Sweep
RCLT HD, fresh install	IFS (Type III or IV)	8	29°	58°
RCLT HD, broken-in	IFS (Type III or IV)	8	32°	64°
1998 4WD 4Runner	IFS, Stock (Type II)	2	30°	60°
2016 4WD 4Runner	IFS, Stock (Type IV)	2	30°	60°
2021 4WD 4Runner	IFS, Stock (Type IV)	2	29.5°	59°
2008 4WD Tacoma	IFS, Stock (Type III)	2	36°	72°
Live Axle Comparison
Marlin's 1980 "Crawler Truck"	8" Toyota Axle with High Steer	4	28.5°	57°
BigMike's 1981 Pickup	8" Diamond Axle with High Steer	4	31°	62°
1985 4Runner	FJ80 + Hellfire Knuckles, High Steer	4	30.5°	61°
1996 FJ80 Land Cruiser	Land Cruiser, Stock	4	32°	64°

Suspension Travel

RCLT HD prides itself in having good articulation for its mid-length design. At only 2.75" wider per side, it achieves 12% more wheel travel than typical 3.50" kits yet is 27% more narrow for better city driving and maneuverability on technical trails. This is possible because our replacement knuckles use horizontal ball joints instead of stock knuckles that use articulation-limiting vertical ball joints.

Alignment Stability is equally important: Our replacement Heavy Duty Knuckles and integrated HD MarRack steering have patented geometry specifically designed for a lift with increased flex, so your alignment geometry does not deflect as much while articulating compared to all other lift kits reusing stock knuckles.

Maximum Travel
at hub centerline Recommended Limit
Strap Setting Knuckle Geometry
designed for a lift

RCLT HD +2.75" LT
Using Low Profile Bump Stops & RCV axles 11.6" 11.0" YES

RCLT HD +2.75" LT
Using Custom Bump Stops & RCV axles 14.0" 13.5" YES

RCLT HD +3.50" LT
Using Low Profile Bump Stops & RCV axles 12.0"* 11.5"* YES

RCLT HD +3.50" LT
Using Custom Bump Stops & RCV axles 14.5"* 14.0"* YES

3.5" values are estimated

The below video shows measurements of both "Easy" and "Best" install methods as per Page 34 of our Installation Guide. Results may vary based on Coilover and Axle type used. See video description for more details.
RCLT HD Owners: Click here to view "Best" method installation tips.

	Maximum Travel at hub centerline	Recommended Limit Strap Setting	Knuckle Geometry designed for a lift
RCLT HD +2.75" LT Using Low Profile Bump Stops & RCV axles	11.6"	11.0"	YES
RCLT HD +2.75" LT Using Custom Bump Stops & RCV axles	14.0"	13.5"	YES
RCLT HD +3.50" LT Using Low Profile Bump Stops & RCV axles	12.0"*	11.5"*	YES
RCLT HD +3.50" LT Using Custom Bump Stops & RCV axles	14.5"*	14.0"*	YES
3.5" values are estimated

Sway Bar

Sorry, but RCLT HD is not compatible with sway bars or Toyota K.D.S.S.

Toyota Safety Sense on 2018 and newer vehicles

All products on this website are intended for Off-road use. RCLT HD prides itself in highly stable geometry resulting in superior drivability compared to other lifted Long Travel setups reusing factory knuckles. Please be aware that if you alter the height of a vehicle equipped with Toyota Safety Sense (MY 2018+) then you may need to recalibrate your vehicle's dynamic radar cruise control, pre-collision with pedestrian detection, and lane tracing assist. Please ask your dealer or contact Toyota Motor Corp. for details.

Traction Control

While RCLT HD is fully compatible with all traction control systems, please bear in mind that a lifted vehicle on larger than stock tires will result in a higher center of gravity that may cause your traction control system to be more active than stock at heavy-acceleration low-speed sharp-cornering during city driving.

Wheel Backspacing

Wheel backspacing should be limited to 4.50" or less due to the nature of our oversized Heavy Duty Knuckle and wide tires desirable for increased traction (i.e. 12.5" wide tires compared to 10.5" stock). If you are partial to 4.75" BS wheels, then you could try 1/4" spacers (example 1, 2) with Extended Thread (ET) lug nuts (example 1).
RCLT HD Owners: Please see thread Compatible Wheel + Tire Combos for more info.

Wheel Diameter

Our steering geometry requires at least 17" wheels. Sorry, 16" wheels are not compatible. Silver linings include many 17" wheel & tire options and Tacoma owners will be able to upgrade to larger brakes (more info).

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BigMike's Q&A to Dirt Lifestyle's RCLT HD Install Video

Click to watch Nate and BigMike discuss RCLT HD on YouTube!

Below are additional answers by BigMike to video comments from Dirt Lifestyle's RCLT HD installation.

BigMike: I'd like to first define the term "Long Travel"
Long Travel (LT) refers to replacing factory lower & upper control arms (LCA & UCA) of an IFS with new arms that are longer than stock. There are much longer LT setups in the world, from Ultra4 to Trophy Trucks, where the LCAs are inboard-mounted close to one another for maximum arm length. But arms from a "LT kit" attach directly to your existing frame mounts as a simple remove-and-replace install. As the arms are longer, we get more suspension travel, articulation, stability, and an improved ride, but at the expense of adding overall width to the vehicle. It's a compromise: Really long arms are great for performance, but the vehicle becomes excessively wide and difficult to drive in cities and narrow 4WD trails. In addition to more flex, longer arms extend further down for the same arm angle providing natural lift without incurring excessive CV joint and steering component angles. This is how we're able to get more lift instead of using a Frame Drop Bracket Kit which negates the ground clearance advantage of IFS.

Q: When will RCLT HD be available?
A: Kits have been shipping since Spring 2021.

Q: What does RCLT HD fit?
A: Type III & IV Toyota IFS frames (2003+ 4Runner/Lexus GX, 2005+ 4WD/PreRunner Tacoma, 2006+ FJ Cruiser).

Q: What makes RCLT HD different from other Toyota LT kits?
A: RCLT HD has created a new market segment and does not directly compete with existing LT kits. Specifically, RCLT HD is the first LT kit designed for Rock Crawling and provides unmatched approach angle, ground clearance, and steering strength. Some of its "firsts" include: (1) First LT with an integrated replacement HD steering rack built with 1-Ton double-sheer components providing more steering power & reduced driver fatigue, proven strong enough for King Of The Hammers (KOH) and 40" tires, (2) First LT to incorporate two-inch forward-mount knuckles, whereby a 35" tire easily clears the body mount frame bracket, 37s fit like 33s, and up to a size 42" tire may be installed without relocating the body mount, (3) First LT to incorporate an inverted lower arm with inset shock mount equaling the ground-clearance gain of going from 31 to 40" tires, (4) First LT strong enough for Rock Crawling, and (5) First LT that challenges the benefits of a Solid Axle Swap (SAS).

The fact "SAS" is even listed on this product page tells you all you need to know.

Q: What frame modifications are required compared to other LT kits?
A: RCLT HD requires a steering rack insert to be welded into the frame.

Q: What skills and equipment are needed to install RCLT HD?
A: "If you can drill a hole and weld upside down, you can install RCLT HD" – Nate, Dirt Lifestyle

Q: How long does it take to install RCLT HD?
A: The experienced mechanic may install RCLT HD in 8 to 12 hours and the first-time home-mechanic should be able to do it in two weekends. Expect an average shop install time to be 2-3 days.

Q: What are the advantages of RCLT HD over an SAS?
A: While RCLT HD was never meant to replace an SAS, it challenges the benefits of an SAS by having vastly more ground clearance, less unsprung mass, is 99% bolt-on, may be removed & transferred vehicle-to-vehicle (ex. if you have a Tacoma now but later switch to a 4Runner), retains factory speedometer/ABS/cruise/traction control systems, no death wobble, reuses original brakes & hub components for ease of service & parts sourcing, can be aligned by any shop without special instructions, and retains superior IFS handling, ride-quality, & stability for daily-drivers.

Q: How does installation of RCLT HD compare to an SAS?
A: Shops typically schedule 2 to 2½ weeks to SAS a Type III/IV frame, whereby RCLT HD can be installed in a couple days. Moreover, the average home mechanic able to install a LT cannot build a custom late-model SAS.

Q: How does the price of RCLT HD compare to an SAS?
A: SAS'ing a late-model Toyota IFS cannot be compared to SAS'ing a 1986 Hilux. Many shops charge $25,000 or more for a turn-key SAS which is more than double a turn-key RCLT HD. When installed at home, a complete turn-key RCLT HD costs less than just an SAS labor charge. If you're unable to install RCLT HD yourself, expect a 2-day shop labor charge to be just over $2,000.

Q: Why is it you didn't want to remove the IFS in favor of a solid axle swap but in the same breath you tore the rear suspension out to go linked and coilovers?
A: Keep in mind that a rear SAS does not require removing the two strongest cross members of the frame (IFS sub-frame), removing existing shock towers, adding at least two new crossmembers (radiator support and under the bellhousing), changing to an entirely new steering type (gear box) with matched panhard-to-tie rod angles, and avoids all the complications of packaging new hydraulic lines, pan hard bar, upper tower & link, and taller shock towers under and around the engine oil pan, exhaust manifolds, and cylinder heads as well as clearancing into the cab and front wheel well which is much more limited and time consuming than simply removing inner fender plastic from the truck bed. As Nate shows, a 3-link conversion to an existing rear solid axle without any engine and steering complications is easier than a front SAS, and he even reused the factory rear leaf spring hangers and avoided cutting the frame entirely! Case in point, shops can do rear 3-links like Nate's in 2 days whereas an SAS to a late-model Toyota can take up to 3 weeks.

Q: What makes RCLT HD cost more than typical LT kits?
A: Simply put, RCLT HD has the most massive and strongest Toyota LT replacement knuckles ever made. This is because our HD Knuckles are made from one-piece solid steel lower sections, where the brake caliper mount, hub, and double-sheer steering arm are all one interconnected solid part. This billet chunk of steel starts out at 50 pounds and is both larger than the billet we use to make our MC08 Dual Case Adapters and requires nearly twice as long to machine. In addition, we use 1/4" plate steel instead of 3/16" and have extra front & rear double-wall plating where stress forces are the highest. When you consider how each knuckle requires more manufacturing than a Dual Case Adapter with additional laser cutting, forming, assembly, welding, and powder coating, you can see how each knuckle is valued at $1,500. Without the knuckles, our retail price would be $3,999, which is on-par with typical LT kits despite our kit also having double-sheer HD upper arms with 1/4" steel plating, double-sheer HD lower arms with 1/4" steel plating, and parts to build and install a replacement HD MarRack with DOM MiniMarlinks, 1-Ton ⁵⁄₈" tie rod ends, and patented steering geometry. (Most all LT kits use single-sheer connections, only 3/16" plating, and are not an integrated HD steering rack upgrade.) Comprised of 248 parts, RCLT HD is the most complex LT kit by a wide margin and I believe it is reasonably priced for what it offers: The strongest and most reliable LT kit ever made with Rock Crawling ability no other LT kit can hold a candle to.

Q: What is the MarRack?
A: The MarRack is an oversized heavy duty steering rack used exclusively with RCLT HD. Originally, we sought to make our own custom Heavy Duty steering rack, however, after working with both Koyo Seiko and JTEKT direct in Japan it was impossible to compete with the low cost of simply modifying an existing rack. So instead, we evolved RCLT HD to work with a Land Cruiser rack which is modified into a MarRack. All parts are transferrable so should you ever need a new MarRack you simply grab an over-the-counter LC rack, convert into a MarRack, and install! See Required Parts tab for more details.

The name "MarRack" is derived from Marlin's traditional nomenclature dating back to the mid-1980s where he invented the MarTack (prevents locker damage at time of axle failure), Marlink (first heavy duty replacement steering tie rod), Marfield (first heavy duty replacement Birfield axle joint), MarJoint (rebuildable uniball), and the 22MAR (one of the first 20/22R engine builds).

NOTE: Due to inferior bushing design and inconsistent high pressure line fitting tolerances, we no longer recommend remanufactured racks or racks with double D bushings. Please see this image for reference.

Top: Factory light-duty steering rack. Bottom: Marlin Crawler MarRack with DOM MiniMarlinks & 7/8-14 X ⁵⁄₈" TREs

Q: How strong is the MarRack?
A: The MarRack is the only DOT-approved steering rack to survive KOH as well as more than 55,000 miles of daily-driving and rock crawling across six-states with 40" tires, Triple Transfer Cases (580:1 Crawl Ratio), F&R lockers, cutting brakes, & never trailed. It has three frame mounts instead of two with M14 mount hardware instead of M12 (2.1 X stronger frame connection), mounts are wider than stock for greater force loading, uses M28 ITRs instead of M14 (4.0 X stronger connection), and is built from a one-piece oversized aluminum housing that is 54% more massive than stock. On top of all this, our HD Knuckle steering geometry reduces load upstream to steering components, so every trail object the MarRack "feels" is reduced by our patented design.

MarRacks have been in use for over 4 years with 35 to 40" tires and have had no reported rack or tie rod failures.

Q: Can the MarRack be used with stock IFS or other LT kits?
A: No. Because the MarRack is derived from a Land Cruiser, which is wider than the mid-size SUV/Tacoma, a new steering, knuckle, and suspension geometry is required for it to work safely & properly. I spent over two years perfecting this geometry to be stable throughout 14-inches of travel and patented the design allowing an oversized rack to work in narrow frames.

Longer answer: From a safety standpoint I am compelled to express further that mismatching IFS geometry may cause injury or property damage as vehicle control is a critical safety aspect that MUST be taken deadly serious.

The narrow mid-size frame width (Tacoma/4Runner/FJ Cruiser/Lexus GX) is NOT compatible with a wider Land Cruiser steering rack. That alone throws off steering geometry. But it's worse: The MarRack sits further forward and higher up in the frame than your stock rack. This incompatible combination results in a host of issues including bump steer, excessive cross-caster, increased brake-dive, and cornering instability. Additionally, your knuckle geometry does not match a Land Cruiser rack so you get a large slip angle (Ackerman) and a lower steering ratio resulting in twitchy steering, dangerous emergency lane changes, and a greater risk of highspeed roll-over. The cherry on top will be excessive front tire wear.

The wider Land Cruiser geometry does not match narrow mid-size applications
The steering system of an IFS is more complex than a Solid Axle and one cannot throw random parts together, tighten shackles to quiet death wobble, and head for the trail. On an IFS, your tires are connected to lighter, more efficient components with built-in dynamic caster & camber that affect toe, so incorrect geometry is more detrimental to driving dynamics than a solid axle. IFS requires careful design to properly integrate with an entirely different steering system. When I first installed a LC rack in 2018 it handled so poorly that I could not go over 40 MPH and almost caused an accident. There is a reason why this had never been done before.

If simply throwing in a MarRack worked and was safe then we would have patented it
For these reasons we do not build our HD Knuckles with reusable jigs in non-temperature controlled rooms, welding together thin plates of steel into hallow steering arms that customer lives depend on. The excellent drive & handling of RCLT HD comes from our HD Knuckles' one-piece solid billet double-sheer steering arms (the first Toyota LT of its kind) with CNC-precision mirror-matched geometry creating the first LT kit geometrically integrated with an oversized steering rack from a larger vehicle.

RCLT HD is the first LT kit with a geometrically integrated oversized steering rack
The result of our patented geometry-stable design is driving characteristics better than any LT kit that reuses stock steering geometry in a lifted application. Customers praise how tight and responsive RCLT HD's steering feels, and a Grandmother could daily-drive RCLT HD with 40" tires and would not need a list of precautions.

RCLT HD's stable geometry has up to 14" of hub travel (+2.75" kit) that
experiences only half a degree camber & toe change through 90% of flex

This is impossible with stock knuckles and a LC rack
Our stable geometry from lift-to-squat results in an exceptional driving experience

Q: Do we offer the MarRack?
A: UPDATE 11/21/2023: Yes, we do! Please visit our 200-series Steering Rack product page for details. Please note that because there is no way we can ensure the installer properly flushed the steering system in order to warranty a MarRack, once the rack has been modified or installed, we are unable to accept it as a warranty or return as we also would not be able to return it to Toyota. Please see the Disclaimer on the product page for more details.

Q: Any power steering pump mods required?
A: No. Our steering geometry increases steering strength, so an increase in pump pressure or cooling is not needed.

Q: Aren't other LT kits used for Rock Crawling?
A: While you could go rock crawling with other kits, none are designed for it. It is well accepted that a 35" tire is the minimum entry size to be taken serious as a Rock Crawler, and because factory inner tie rods fail with 33s, knuckles bend with 34s, and steering racks die with 35s, there is no Rock Crawling LT kit. In fact, other LT manufactures advise against technical rock crawling altogether. We are not only confident in technical Rock Crawling RCLT HD with tires up to and including 40", but our patented design provides SAS-like approach angles, increases ground clearance beyond other kits, and has steering and knuckle strength proven strong enough for KOH underneath 4.7L V8 4Runners. We are achieving this with non-upgraded factory MarRack inner tie rods (ITR) and have yet to bend or break a single one, even with 40s. RCLT HD is in a league its own when it comes to IFS Rock Crawling capability and performance.

Q: What's the point of all this strength when you've still got the front IFS differential?
A: We covered this from the 19:55 to 22:01 min video mark, but another thing to add is that the reverse-rotation high-pinion 8" Type III/IV IFS differential uses the same R&P from the 100-series 4.7L V8 Land Cruiser, which is the same R&P as the venerable and popular 80-series High Pinion except it's even stronger due to it having a wider & thicker ring gear. So the SUV/Tacoma 2003+ front IFS differential is (1) stronger than the Toyota Solid Axle 8" High Pinion, (2) is from a V8 Land Cruiser, and (3) has well been proven strong. The strength or reliability of my front diff has never crossed my mind throughout my entire 55,000 miles of daily driving and Rock Crawling with the same front diff, a 580:1 Crawl Ratio, and 40" tire/wheel combo that weighs 145 lbs each.

Q: Can RCLT HD be used for High Speed?
A: Absolutely, as proven at KOH. However, please bear in mind that our design is optimized for rock crawling strength & performance. Therefore, (1) our parts are heavy which reduces high speed efficiency and (2) because our lower arms are optimized for ground clearance, spacing is tight around the outer CV boots at full droop. See Instructions | Appendex A13: "High Speed Use Tips" for more details.

Q: Can RCLT HD be installed onto a non-USDM Hilux/Surf Toyota vehicle?
A: So long as the vehicle shares the same Prado 120/150-series IFS, then there is a good chance it can. Also, the MarRack can be made for LH or RH configurations. The only unknown variable is space beneath non-USDM engines such as turbo diesels, so oil pan modifications may be required to clear the oversized steering rack.

Q: Can I use a Big Brake Kit on RCLT HD?
A: Customers have successfully installed oversized Wilwood, CEIKA, and OEM brakes with RCLT HD. I run oversized Lexus GX460 brakes on my Tacoma. It is known that 6-piston AlconUSA and StopTech brackets must be modified for speed sensor and knuckle upright fitment.
RCLT HD Owners: Please see this thread for more info on aftermarket brake kit compatability: Big Brake kit

Kits shipped since summer 2022: Our HD Knuckles now use Toyota's larger M14 caliper hardware found on 2015 and newer SUV applications. This means 2014 and older SUVs and all Tacoma applications will need to order four Toyota 90105-14198 caliper bolts and upgrade existing caliper through-holes using ⁹⁄₁₆" drill. Each caliper flange has a lot of surface area and drilling one size up has no impact to safety or brake performance. (Optionally, you may choose to upgrade to larger 2015+ 4Runner/GX460 M14 calipers with matching 2010+ 4Runner/GX460 rotors for an OEM "Big Brake" setup.)

Six-piston Wilwood and CEIKA brake upgrades with RCLT HD

Q: How much travel to expect from RCLT HD?
A: This depends on how much up-travel you're looking to have, pending tire size and clearancing plans (see "Bump Stop Consideration" Page 34 of our Online Instructions). For example, on Nate's +3.50" setup, he is intentionally limiting up-travel to minimize 38" tire clearancing requirements, and is only expecting about 12" of travel. On my shorter +2.75" setup, I get 14" of travel at hub centerline because I relocated my bump stops. This is why we did not cover this in the video because Nate is not sure how things will turn out pending his fiberglass fender install. He has a lot more down travel than I do so if he did the same amount of clearancing as I did then I'd expect him to have around 16" of travel.

RCLT HD (+2.75) achieves up to 14" of travel at the hub. Click here for more info

Q: How close are the 2nd & 3rd gen Tacoma front suspensions?
A: See Appendix A6 of RCLT HD's Installation Guide.

Q: Are factory and aftermarket skid plates compatible with RCLT HD?
A: As far as we know all skid plates, stock and aftermarket, are compatible with RCLT HD. Update 8/3/2022: Skid plates that utilize the M12 bolt hole in front of the factory steering rack's LH frame mount may require modification to work.

Q: How long will the uniballs last?
A: While uniballs do not last as long as sealed joints, I did not want to settle on anything less than the ultimate strength of double-sheer top-and-bottom mounts which means uniballs are the only option. How long they last depends on mileage and climate type. For daily driving in dry climates, expect them to last 5 years or more. For daily driving in cold climates where road treatments like salt are used, we've heard they may only last up to 1 year. We use 1" high quality USA-made FK Uniballs. Rebuild kits are currently available by phone.

Q: Do you have to relocate headlights in order to run 40" tires?
A: When I allowed my TacomaWorld forum thread to get hijacked last year, some user who has never ran a LT with 40s claimed I relocated my headlights in order for this to work. He is mistaken as I run my 8" Radflo shocks (p/n 6CT-001-5A) to full compression and all my components are in their stock location, including headlights and battery.

Q: How is the ground clearance comparison fair when Nate's Tacoma is on jack-stands?
A: Nate can easily set his ride height to match what's shown, and also the Jeep is on taller 39" tires while the Taco is only on 38s!!

Q: Will Nate's truck be at the 2022 KOH?
A: Hopefully yes and come see it & meet Nate in person at our Marlin Crawler booth!

Q: How did Mike like Nate's coffee?
A: It was delicious and was served in a stainless tumbler with "Dirt Lifestyle" logo!

RCLT HD with 40x13.5" tires under a 2016 V6 Toyota Tacoma
More than 45K miles of testing with 40s and zero steering, axle, or differential failures

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North American IFS Types for Toyota Mid-size Pickups and SUVs

To help understand the differences of the Toyota IFS 4WD, please see the following section which comes from our Instructions, Appendix A6.

	IFS Type I 1986-1995	IFS Type II 1995-2004	IFS Type III 2003-2015	IFS Type IV 2010-2023
RCLT HD Compatible:	No	No	YES	YES
Applications:	1986-95 Hilux 1986-95 4Runner	1995-04 Tacoma 1996-02 4Runner	2003-09 4Runner 2003-09 GX470 2010+ GX460 2005-15 Tacoma 2006-09 FJ Cruiser	2010+ 4Runner 2010-14 FJ Cruiser 2016+ Tacoma
Spring Type:	Torsion Bar	Coil over	Coil over	Coil over
Differential:	Standard	Standard	Clamshell	Clamshell
R & P Size:	7.5"	7.5"	8.0"	8.0"
Rotation:	Standard	Reverse	Reverse	Reverse
Source:	1979 2WD Pickup	Land Cruiser Prado 90-series	Land Cruiser (V8) Prado 120-series	Land Cruiser (V8) Prado 120-series
Steering:	Gear Box	Rack & Pinion	Rack & Pinion	Rack & Pinion
Location:	In front of axle	Behind axle	In front of axle	In front of axle
Outer CV:	Bell OD: 93mm Splines: 26	Bell OD: 94.5mm Splines: 30	Bell OD: 106mm Splines: 30	Bell OD: 106mm Splines: 30
Inner Shaft:	OD: 23.75mm	OD: 29mm	OD: 32mm	OD: 32mm
Hubs:	Manual or Automatic	Manual or Non-selectable	Non-selectable	Non-selectable
Brake Rotor:	OD: 289 to 291mm Thick: 20 to 25mm	OD: 296 to 319mm Thick: 22mm	OD: 319 to 338mm Thick: 28mm	OD: 319 to 338mm Thick: 28 to 32mm
LCA Design:	Hilux	Land Cruiser Prado 90-series	Land Cruiser Prado 120-series	Land Cruiser Prado 150-series
Bump stops:	2 per side	2 per side	1 per side	1 per side

Marlin Crawler's Take

Type I: The first 4WD IFS offered in the States left a lot to be desired. The use of a torsion bar limited lift options and resulted in a squeaky off-road experience. While it used a traditional and robust steering box, the idler arm and small tie rods were prone to failure. Small axle shafts with no HD Rock Crawling upgrade options, and a small front R&P lifted from a 1979 2WD pickup.
Largest recommended Rock Crawling tire size: 32".

Type II: The Prado 90-series was a major upgrade for IFS 4WD Toyotas. Designed by Toyota's commercial truck division Hino Motors, this IFS features easy to change coil overs, axles with available HD aftermarket upgrades, improved reverse-rotation high-pinion R&P, and a steering rack mounted favorably behind the axle for improved forward-direction strength, it had potential.
Largest recommended Rock Crawling tire size: 33".

Type III: The Prado 120-series IFS essentially doubled the strength of Type II in every category except steering. The differential became larger and adopted an improved clamshell design which orientates assembly bolts perpendicular to the pinion resulting in much greater pinion deflection resistance. The R&P is the same used in the larger 8cyl 100-series Land Cruiser and proven reliable with 40" tires. Heavy Duty aftermarket axle options include inboard & outboard 35-spline Dana-60-sized CV joints that include a manufacture guarantee to not fail with tire sizes up to 40" in diameter.
Largest recommended Rock Crawling tire size: 35" with proper attention to steering & knuckle strength.

Type IV: The Prado 150-series IFS further builds upon the Type III by featuring larger and stronger lower control arm mounting hardware. In some SUV applications, the brake rotors are 6% larger and 28% thicker, and calipers have 28% more piston area with 36% stronger knuckle mount hardware. Steering strength unfortunately remains the major weak-link of the mid-size Toyota IFS.
Largest recommended Rock Crawling tire size: 35" with proper attention to steering & knuckle strength.

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Prototyping and Testing

As of 2022, iterations of RCLT HD have been tested on the following trails without failure:

On 40" x 13.5" tires:

Over 55,000 miles of daily driving and highway use
without any steering or suspension failures

Northern California:

Rubicon (6-times)
Fordyce (entire trail both ways without winching)

Central California:
Dusy/Ershim (5-times, both directions)
Coyote Lake
Red Lake
Strawberry Lake
West Lake
Bald Mtn
Cheapo Saddle

Colorado:
Poughkeepsie Gulch
Imogene Pass
Black Bear Pass
Moab, Utah:
Pritchett Canyon
Hell's Revenge
Cliff Hanger
Metal Masher
Top Of The World
Kokopelli
Flat Iron Mesa
Poison Spider
Where Eagles Dare
Golden Spike
Moab Rim
Elephant Hill
Fins & Things
Onion Creek
7-Mile Rim

Southern Utah:
Hole In The Rock

On 35" x 12.5" tires:
Southern California/Johnson Valley:
Sledge Hammer
Jack Hammer
Aftershock
Fissure Mtn
Not Her Problem
Guacamole
Cougar Buttes

RCLT HD Installation and Action Example Pictures

Bookmark link: MarlinCrawler.com/RCLTHD/media
Click to view Instagram posts for #RCLTHD

Below are RCLT HD Install Pics on various rigs, grouped by tire size. In general, 315 or 35" tires are great for the all-around daily driver plus weekend warrior platform, requiring none or very minimal trimming or up-travel limitation, 37" and 38" are what the more adventurous refer to as "The new 35s", requiring more clearancing to get the full effect yet while retaining city driving practicality, and running 40s is what extreme people do for insane IFS capability, who aren't afraid to cut fender lines and cab material, made possible thanks to the high strength of RCLT HD Knuckles + MarRack Steering, combined with RCV Ultimate Axles for a bulletproof setup that we have yet to see fail on any application.

SUV Install Pics

2003-2009 Land Cruiser Prado

2003-2009 4^th gen 4Runner

2010+ 5^th gen 4Runner

2006+ FJ Cruiser

2003-2009 Lexus GX470

2010+ Lexus GX460

Truck Install Pics

2005-2015 2^nd gen Tacoma

2015+ 3^rd gen Tacoma

2003-2009 Land Cruiser Prado

Right-hand drive

On 33" Tires

LC Prado on 255/80R17 (+2.75") @kazuki_0203

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2003-2009 4^th gen 4Runner

On 315s / 35" Tires

4G 4Runner on 35s (+2.75") @t4rventure

On 37" Tires

4G 4Runner on 37s (+2.75") @lostinthewoodst4r

3G Taco on 40s (+2.75"), 4G 4R on 37s (+2.75")

4G 4Runner on 35s (+2.75") @t4rventure

On 40" Tires

4G 4Runner on 40s (+2.75") @4xfredwilliams

3G Tacoma on 40s (+2.75") flexing atop 4G 4Runner on 40s (+2.75")

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