Toyota 8.4″  2004 & Older Completely Assembled Differential equipped with a Spool Locker. Fits trucks with the 60mm x 60mm pinion flange pattern.

A Spool is a device that completely replaces the inner workings of the differential. The ability for the differential to differentiate torque distribution between axle shafts is entirely removed. The result is a fully locked axle where both axles receive the same amount of torque regardless of available traction, load, or amount of throttle applied. Spools cannot be unlocked; The axle becomes locked all the time.

Spools are extremely strong and maintenance free as all moving parts are replaced with one solid spool. The ring gear simply bolts to the spool, both axle shafts connect directly to it, and the whole assembly is held in place by the carrier bearings. This is the strongest possible differential available with the lowest possibility of failure.

The downside to a spool-locked differential is that it’s locked all the time. Therefore its use is mainly limited to buggies or trailer rigs that don’t see any daily driving or highway miles. Keep in mind that running a spool in the front axle will limit your steering ability depending on which tire has the highest amount of traction (inside corner tire or outside corner tire). In general when a spool is used in the front axle your turning radius will increase. But it’s always locked when you need it, there are no moving parts, and there is nothing to go wrong due to its high level of strength!

All 3rd members are assembled with trail proven Yukon R&P gears, new high quality Yukon setup kit with Japanese bearings, new Yukon Spool locker, our Heavy Duty EcoSeal pinion seal, our Heavy Duty pinion flange, and our Heavy Duty solid spacer kit where applicable. Please follow our R&P break in procedure to maximize the life of your new 3rd member.