Is this safe to use at this point? (99' GT, 75k Miles, No problems). Everyone I ask has a different story on a syn. ATF. My take is that if it meets Dextron III standards, it can be used. Any ideas on this? Have 10Qs laying around and would like to use it. Was gonna drain what I have, change the filter, and use the Mobil 1 with some Trans-X or something like that. A lot of people say this will cause slipping though?


Thanks, any help greatly appriciated!
Mike

I'm going to play the Devil's advocate and say no considering your mileage. Sometimes it's better to leave well enough alone or if it ain't broke then don't fix it. Go with the Dextron-III.








http://i5.photobucket.com/albums/y186/lizzywiz/gtp.jpg
Thrasher CAI, DHP v1.0 PCM, SLP Headers,
3.25 SC pulley, CAIT GMAF, 2.5 DP/Hi-Flow CAT,
u-bend delete, 160 TS, ZZP Stage 1 72mm TB,
TB spacer, MSD 8.5mm wires, Autolite 103,
Goodyear Gatorback Serp. & SC Belt,
Nitto NT555R Drag Radials
1/4 ET: 13.210 sec. @ 104.490 mph
0 - 60 ft: 1.945 sec.

I agree with Bnaylor, and wouldn't change to synthetic at this point. Synthetics actually flow slightly thinner than their conventional counterparts, and can cause leaks and/or slipping in a trans that has decent mileage on conventional fluid. I have never used synthetics, and have never had a serious engine or trans problem. My 91 Grand Prix winter beater that I just sold has 240k on it and still runs and shifts like new. I just don't see the advantage of the higher priced synthetics. just my :2cents: