Yukon Gear Master Overhaul Kit For Toyota Tacoma and 4-Runner w/ Factory Electric Locker

A Tacoma, 4Runner or T100 with the factory electric rear locker that has started to whine between 40 and 60 mph, clunks when you get on and off the throttle, or needs new gears after a tire upgrade needs a bearing kit made for the locker carrier, not the open-diff kit. The Yukon YK TACOMA-LOC is that kit: a new master overhaul set with Timken bearings and races for the Toyota 8-inch rear that came with the factory E-locker.

What is in the YK TACOMA-LOC

• Carrier bearings and races
• Pinion bearings and races
• Pinion seal and pinion nut
• Crush sleeve
• Complete shim kit
• Ring gear bolts
• Oil baffles and slingers
• Thread locker, marking compound with brush, and silicone

What the kit does in a locker-equipped Toyota 8-inch

The Toyota 8-inch is a third-member axle: the pinion, carrier and bearings come out of the housing as one unit. On trucks with the factory E-locker, that carrier is a different part from the open carrier, with its own side bearings and an electric actuator that slides a collar to lock the side gears together. Because the carrier bearings differ, an open-diff overhaul kit does not cover it. This kit replaces every bearing that sets gear position, so you can rebuild the original gears or set up new ones and get a correct contact pattern. The ring gear bolts and the slingers and baffles are included, which saves a parts run when the third member is on the bench.

Symptoms that point to worn bearings

• A whine that rises and falls with throttle, typical of pinion bearings that have lost preload
• Clunk or in-and-out play at the pinion yoke, a sign the crush sleeve has relaxed
• Rumble that changes on decel, or noise that started after a regear
• Gear oil leaking at the pinion seal
• Metal glitter on the fill plug or drain plug magnet

How to confirm before you buy

First rule out the wheel bearings: a hum that tracks road speed rather than throttle, and changes in turns, is usually an axle bearing. Then grab the pinion yoke and check for play, and drain the oil to look for metal. Our differential whine diagnosis guide separates the noises. If the complaint is that the locker will not engage rather than noise, check the wiring, actuator and switch conditions first, covered in our locker not engaging guide; a bearing kit will not fix an actuator.

Fitment

Yukon lists this kit for Toyota Tacoma and T100 rears with the factory locking differential, and retail catalogs place it in 1993-2015 Tacoma, T100 and 4Runner applications. Toyota built the 8-inch in 4-cylinder and V6 versions with different pinion sizes, and later 4Runners moved to an 8.2-inch rear, while 2016-and-up Tacomas with the locker use a larger 8.75-inch rear. Confirm the bridged bearing caps of the locker housing, the axle tag and the pinion spline count, or send us your year and VIN and we will check it. For an open-diff 8-inch, use the Toyota 8-inch open-carrier overhaul kit; for a 4Runner or FJ 8.2 with the factory locker, use the 8.2 factory-locker master kit. Our Toyota 8-inch guide explains the versions.

Install notes

• Mark the bearing caps and record the original pinion shim and backlash before teardown.
• Revolution Gear's setup chart lists the Toyota 8-inch rear at 12-15 in-lb pinion bearing preload, .006-.010 in. backlash, and 70 ft-lb on both ring gear bolts and bearing caps, with a 0.074 in. starting pinion shim.
• Crush the new sleeve slowly and check turning torque often; overshooting preload means a new sleeve.
• Use thread locker on the ring gear bolts and confirm the pattern with the marking compound.
• Regearing at the same time? Pick the set that matches your pinion, such as the V6 29-spline 4.88 ring and pinion or the 4-cylinder 27-spline 4.88 set. A bearing race and seal driver set makes the races go in square.
• Seal the third member with the supplied silicone, refill with the gear oil grade listed for your truck, and follow a new gear break-in if you installed new gears.

Does this fit a Tacoma without the electric locker?

No. The open-diff carrier uses different side bearings. Use the Toyota 8-inch open-carrier master overhaul kit instead.

Will it fit a 2016 or newer Tacoma with the rear locker?

The 2016-and-up locker trucks use a larger 8.75-inch rear, which this kit is not listed for. Send us your VIN and we will confirm the right parts.

Are ring gear bolts included?

Yes. The kit lists ring gear bolts along with carrier and pinion bearings and races, pinion seal, shim kit, pinion nut, crush sleeve, oil baffles and slingers, thread locker, marking compound and silicone.

What bearings are in the kit?

Yukon specifies Timken bearings and races in the YK TACOMA-LOC.

Can I reuse my original ring and pinion?

Yes, if the teeth are not pitted or chipped. Record the original shim and backlash, rebuild to the same numbers, and confirm the pattern with the marking compound.