Rear end fluid change: when?

[zgirl8]

I was wondering if/when I should change the rear end fluid? I have a '95 Z with 160K. I've never had any problems with the rear end...should I wait until I do or change it now to prevent problems later?

[FANTA-Z]

If it hasnt been changed I would think about doing it now

[zgirl8]

Thanks FantaZ! What about the tranny fluid (T-56)? I saw in a post that you had switched to Mobil1 in your T-56 and noticed a temp difference. How can you tell w/o a gauge, was the difference so big you can just feel it from the inside? Mobil1 or not, should I go ahead and change the tranny fluid, too, do you think?

[MK-Z28]

Yeah that has needed to be changed for awhile. I am not to sure on the T56 because i have a auto but Mobil 1 should be ok. That is great oil.

[FANTA-Z]

Yeah you could actually feel the difference in the car from the heat. Although after I talked to the guys that bulletproofed my T56 he suggested not putting synthetic oil in the tranny so I have since then switched back to conventional auto tranny fluid.

[FreakassLT1]

Originally Posted by FANTA-Z

Yeah you could actually feel the difference in the car from the heat. Although after I talked to the guys that bulletproofed my T56 he suggested not putting synthetic oil in the tranny so I have since then switched back to conventional auto tranny fluid.

how does that work?

[Wicked94Z]

its what they use. some transmissions use 10w30 motor oil, some use gear oil, some use atf. just depends on the trans.

[BlackY2kZ28]

oops i have snythetic trick shift in my auto

[titter]

conventional is very good to use to break in the new tranny ... after that i switched to synthetic. automatics need to stay cool ... this helps out a ton! my tranny barely sees above 165-170 under harsh driving conditions now.

[Zlvr95]

Gm Recommends atf in the t56

[BlackY2kZ28]

confused so do you use synthetic or conventional

[titter]

i use synthetic now, with no issues.

[BlackY2kZ28]

Originally Posted by titter

i use synthetic now, with no issues.

ok cool i guess i will do the same from now on

[Raoul-Duke]

i have a thunderracing girdle on my rear end....isnt there a plug on it and where is it located cuz i couldnt see it??

[lola m anderson]

If you have a auburn differential shy away from synthtics, they do not recommend its use. Any brand name 80w-90 gear oil will work fine. If you can find chevron 80w-90LS or mobil 80w-90LS, or white bottle Valvoline, you will not/should not need to add the friction modifier, maybe a 1oz or 2 if it is a brand new carrier.

If using a gear oil without the friction modifier add 3 oz per quart of gear oil, you can get it at any GM dealer, or Ford dealer (sorry for cursing), its the exact same suff. IF your differential is of high mileage or severe duty kick it up a notch to 85w-140 in the warm/hot weather

Hope it helps shout back