Synthetic Tranny Fluid

[mikesarebetter]

recently bought a 2003 gtp with 58k miles on it. looking to change out the tranny fluid. i have access to free mobil 1 full synthetic atf. was curious if anyone knows will this work fine with current tranny fluid as i don't want to take the time and effort to flush it. just dump it and change the filter while i'm there. any input would be great!!

also... anyone running a zzp pcm on this year gtp? i know it changes shift points a bit but it seems like it dances around alot on low load, always wanting to be in the lowest gear even with a feather on the throttle.. anything similiar from anyone?

 

[Zef_66]

recently bought a 2003 gtp with 58k miles on it. looking to change out the tranny fluid. i have access to free mobil 1 full synthetic atf. was curious if anyone knows will this work fine with current tranny fluid as i don't want to take the time and effort to flush it. just dump it and change the filter while i'm there. any input would be great!!

If the fluid is free, as long as it is Dexron VI, I would go for it. Shouldn't be any problem.

 

[mikesarebetter]

ok thats where my question was i guess... why does it have to be dexron? it's just mobil 1 synthetic atf.. doesn't state dexron.. comin out of a 55 gallon barrel

 

[mikesarebetter]

nevermind.. called mobil themselves and they said that their regular synthetic atf fluid meets and exceeds all standards of dexron 3 wether it says dexron fluid on it or not. guess i'll pour it in

 

[Trannyman95]

You should be safe with it, especially since you are mixing it with your existing fluid. Some guys have mentioned doing a flush/complete fluid transfer with full synthetic trans fluid and having slippage problems so drive it easy for a while so the pcm can adjust to this as it constantly monitors shift timing and should be able to compensate for it if your run into this but it will take a number of driving cycles to make a noticable change-and again that is only if you encounter this scenario.