85-140 Conventional w/ Modifer in my rear end.
05-24-2007, 08:29 PM
#1
3rd Gear Member
Thread Starter
Join Date: Oct 2006
Location: Valley of the Sun
Posts: 824
85-140 Conventional w/ Modifer in my rear end.
Got my gears changed to 3.73s 2 days ago. Got about 40~ miles on them. The guy who put them in used 85-140 Conventonal with FRPP posi modifier stating that synthetic is not recommended for gear break in and that, "When the rear heats up the 85-140 will break down to 75-90" in his words. I've got 3 qts of RP Max Gear 75-90 sitting in the garage and the thought of that heavy-weight 85-140 is bugging the hell out of me.
Should I put some more miles on the rear with the crap that is in there before I drain/change? Also, is there a diff gasket I have to get first or does it use just RTV? I've got some Hi-Temp RTV, but I'll have to grab another gasket if needed. Thanks!
Should I put some more miles on the rear with the crap that is in there before I drain/change? Also, is there a diff gasket I have to get first or does it use just RTV? I've got some Hi-Temp RTV, but I'll have to grab another gasket if needed. Thanks!
05-24-2007, 09:51 PM
#3
5th Gear Member
Join Date: Jul 2006
Location: Miami, FL
Posts: 2,284
RE: 85-140 Conventional w/ Modifer in my rear end.
When I did my gears, I just put the RP right in after installing them. I haven't had any problems. I would say go ahead and change it. I don't see how that other oil will "break down to 75-90" that doesn't make sense to me.
Edit: Forgot to add that I just used some high-temp RTV gasket maker.
Edit: Forgot to add that I just used some high-temp RTV gasket maker.
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