Gear Oil for '85 CJ7

tomve · #1 (**permalink**) 05-15-2005, 05:14 PM

It's time for the gear oil to be changed out in my '85 CJ7. I have a Dana 30 w/arb lockers, 4.10 gears, in front, & AMC 20 w/arb lockers, 4.10 gears in the rear. I have a couple of questions I hope I can get answered. The first, is what viscosity oil should I use? 75w-90 or 85w-140? The second, do the differential covers and gaskets need to sealed with any gasket sealer (ie. RTV Silicone)?
Thanks for the help, Tom

snowdog · #2 (**permalink**) 05-15-2005, 05:31 PM

on that note i have the stock gears in a 79' CJ7 with quadratrac what oil do i use in the diff's?

GaryMB · #3 (**permalink**) 05-15-2005, 07:16 PM

Almost any differential will take 80w-90, with the exception of a few that require special oils such as limited slips. I would check out the arb website to see if their air lockers require special lubricants.

snowdog · #4 (**permalink**) 05-15-2005, 08:31 PM

while we're on the subject of oil. i have quadratrac what do i use in the x-fer case?

jay79cj7 · #5 (**permalink**) 05-15-2005, 10:58 PM

If you want the quadratrac transfer case to keep working, you need to use the special quadratrac lube. This is one of the reasons that this case does not have the best of reputations. Put in ATF or gear oil like other boxes and it won't work right. This full time 4wd case has what is essentially a limited slip differential and needs the special lube to work right, or not wear out. (Not sure which, maybe both.) I have a part-time conversion kit in mine (previous owner), so I just use ATF, and can't point you to where to get the special stuff. I know I have seen it online, and its not too expensive. The Jeep dealer might still stock it as well.

snowdog · #6 (**permalink**) 05-16-2005, 05:51 AM

i know thats its made by chrysler