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  • 3/8 and 1/2 drive sockets, ratchets and extensions.
  • cheater bar
  • catch pan for diff fluid
  • jack and 4 stands
  • torque wrench
  • URL to service manual for torque specs and anything I missed
  • Toyota 3rd member gasket. you can also use FIPG or suitable RTV in place of the gasket. both can be purchased at you dealer but will have a better price.
  • rebuilt or re geared 3rd member

The standard DIY disclaimer applies, don't blame me if you break something or hurt your self doing this, know your limits. If possible having an extra set of hands is very helpful however this can be done solo.

Drain Rear Diff - drive for a few minutes to warm the gear oil. remove the fill plug (top) first then the drain (bottom), the plugs are 24mm (15/16 will also work). keep track of the sealing washers, if you didn't get spares it's ok to reuse them.

Loosen Lugs on Rear Tires

Lift and support rear of the vehicle - chock front tires, lift and support with jack stands, then remove wheels and set aside.

Remove Rear Brakes - unbolt the caliper brackets from the inside of the hub, the bolts are 17mm. suspend complete brake assembly from the frame, do not let the caliper hang by the brake line.

Loosen Brake Lines - unbolt the hard lines from the rear of the axle, bolts are 12mm. next unbolt the e-brake line from the frame.

Disconnect Wheel Speed Sensor - unhook the plastic clip on the wiring harness.

Pull Axles - unbolt the axle nuts from the inside of the hub, these are 17mm and there are 4 per side. you should now be able to slide the axles toward you a few inches, support them with stands and take care not to damage the axle seals.

Disconnect Drive Shaft - loosen the 4 drive shaft bolts and suspend it from the bracket above, bolts and nuts are 14mm.

Disconnect Sway Bar - unbolt the sway bar brackets from the mounts on the front of the rear axle and swing it up and out of the way. the bolts are 12mm.

Free up the Axles - slide the axles out about 3 or 4 inches to clear the splines inside the 3rd member, keep them supported with jack stands. take care not to stress the brake lines too much, remember they are still connected but you can move the axles out enough without opening the hydraulic lines. you will need to pull axles out about an inch more than shown in the pic above.

E-Locker - unbolt the locker cover and the locker from the 3rd member and disconnect the wire harness. some have reported that you can remove the 3rd with the locker still in place but i didn't have any luck and since you will be transferring to the new 3rd it has to come off anyway.

Unbolt the 3rd Member - remove the 9 nuts around the perimeter of the 3rd. these are 12mm and they have a small washer behind them. you should now be able to pull the unit away from the axle and swing it down and out. when you get it out take note of lockers position as it will need to be re-installed in the same position.

Transfer Parts - loosen the e-locker switch on the top of the diff and transfer it to the new 3rd. 1 1/16 should do the trick, not sure what that is in mm.

Axle Clean Up - this was my lease favorite part. clean all the old gasket material from the axle housing. i used a razor, brass brush and brake cleaner. take care not to gouge the mating surface. when you are done, especially if you broke your gears, religiously clean the inside of the axle housing.

Reinstall 3rd Member - give the mating surface one more spray with brake cleaner as well as the gasket surface on the diff. install your new gasket on the axle and you are almost ready to swing the 3rd back up in there. set the locker to position it was in when it came out, you can slide it back and forth by hand to engage and disengage. swing the 3rd back up and onto the axle studs then attach the 9 12mm washers and nuts around the perimeter of the diff. tighten them in a cross pattern to apply even pressure and torque to 18 lb/ft.



Reinstall e-locker - don't worry if you needed to lock or unlock while the 3rd while is in the axle housing. even with the 3rd installed you can still reach the locker gear and the fork to engage or disengage. set it to the correct position. inspect the o ring and attach the e-locker motor. rotate counter clockwise to set the knock pin all the way to the left, torque bolts to 20 lb/ft. connect the wiring harness.

Reattach the Drive Shaft - before attaching the drive shaft bolts apply thread lock (green if you've got it red if you don't) and torque to 65 lb/ft.

Re-install Axles - clean and re grease the axle seals on the back side of the brake assembly and the o ring on the axle side. slide the axles back in reattach the 17mm nuts to the back of the brake assembly. torque to 89 lb/ft.

As much as I didn't want to say it, from here on out assembly is reverse of removal. bolt your brake lines back up and reattach the wheel speed sensors. reattach the brake caliper assembly and torque to 78 lb/ft. attach sway bar bracket bolts. re-install and torque your wheels, i like 85 lb/ft.

Fill Diff - clean the drain and fill plugs, be sure to get all metallic particles off the magnet on the drain plug then install and torque to 36 lb/ft. with the wheels on and back on level ground fill with a quality gear oil 75w90 or 75w140 (API), GL-5. 80w90 can also be used. add oil until it begins to ooze out of the fill hole. torque fill plug to 36 lb/ft.

Gear Break In - there are a couple techniques for breaking in a new gear set. i chose to follow the heat cycle method where you drive at varying speed under 60 MPH for 15-20 miles then stop and let the diff cool for at least 15 minutes, i waited 30. repeat the process another time and then take it easy for the next 500 miles, no towing. when you hit the 500 mile mark change the fluid to remove any metal from the break in process.
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