Transfer case& diff'l oil ?

Tailfeathers · #1 (**permalink**) 08-21-2008, 10:18 AM

Hi all,
The specs state that I should replace the oil in the transfer case with 75W-90 weight gear oil and straight 90 in the rear end differential . Would it be a big deal if I used 80-90 in the transfer case? I am having a hard time getting 75-90 in gallon jugs and I can't find straight 90 weight gear oil.
Thanks

INDYMAC · #2 (**permalink**) 08-21-2008, 12:05 PM

Mobil, Valvoline, and Castrol all make 1 qt bottles of synthetic 75W-90. It takes around 3 qts to do the front diff and transaxle. The qt bottles usually have easy to squirt nipple ends too.
The old SAE 90 is the new SAE 110 (SAE J306 specs). SAE 110 is difficult to find, but not impossible. I use LE 1605 in the rear diff (Rick's Duolec 1605 Gear Lubricant).
AMSOIL SVT 75W-110 would be a great choice also.

BAD BONEZ BJ · #3 (**permalink**) 08-21-2008, 08:57 PM

Read the STICKY's at the top of this forum, there is a DIY section that addresses the diffs and transfer case oil changes, with pics too, so you can't get lost. I personally use Royal Purple 75W-90 in all, but that is just what I found works best for me. You can use what you want, it's your truck.
BJ