After reading several threads on this forum and the other forum I decided to change out my front/rear differential gear oil, transfer case gear oil, and grease the driveshaft.
The process was easier than I thought it would be for my first go around. I'm very happy I did this myself because the gear oils were dark, worst being the front diff, t-case, then rear diff. The u-joints on the driveshaft needed more grease, they "seemed" empty to me. Because of what I've read regarding over-greasing the slip yokes I decided to go with the recommended 3-5 pumps.
I used synthetic Mobil 1 75W-90 all around for the gear oils and synthetic Mobil 1 grease (pink stuff) for the driveshaft.
I didn't take any pictures because you can find plenty of them on the forums. If anyone wants to do this themselves, here is what you will need:
Differentials/Transfer Case
- 6-7 quarts Mobil 1 75W-90
- 5' tubing or gear oil pump
- 24mm or 15/16" socket - for rear diff and t-case
- 10mm hex key socket - for front diff
- 13mm socket w/3" extension - to remove rear skid plate for access to the front diff
- breaker bar
- torque wrench
- large oil pan
Always remove the filler plug before the drain plug. I started with the rear diff. Drain then torque the drain plug to 36 ft-lb (per repair manual). Fill to just below the fill plug opening (0-5mm from the bottom of the opening per repair manual). Torque the filler plug to 36 ft-lb.
Drain t-case and torque the drain plug to 27 ft-lb. Fill 0-5mm below fill plug opening. Torque the fill plug to 27 ft-lb.
Front diff. Remove rear skid by removing 6 retaining bolts -- two up front, two to access the engine oil drain, and two at the rear. Pull skid towards the rear or front (I can't remember) of the vehicle to remove. The fill & drain plugs will be on the driver's side. Drain and torque the drain plug to 48 ft-lb. Torque the fill plug to 29 ft-lb. Do not reattach skid plate.
Driveshaft
- Mobil 1 grease
- grease gun
There are 4 zerk fittings to grease the u-joints. One on the front driveshaft (near the front diff - why I didn't reattach the skid plate), second is before the front of the t-case, third is after the rear of the t-case, and the fourth is at the rear driveshaft (near the rear diff). Attach the the grease gun to each zerk and gently pump away until you see the pink Mobil 1 grease expressing from the u-joints to pump the old stuff out. You will hear a crackling noise when it starts to express. Wipe clean.
There are 2 slip yoke fittings to grease. One is next to the second zerk fitting before the front of the t-case and the second is next to the third zerk fitting after the t-case. I only applied 3-5 pumps of Mobil 1 grease because I was afraid of locking up the driveshaft by over-greasing. I also applied a thin layer of grease to the driveshaft body where it enters/exits the slip yoke. Reattach the skid plate and you're done!
This is actually quite easy to do for a first-timer. The hardest part was removing the grease gun from the zerk fittings. Now I need to learn how to change my own engine oil :biggrin2:
