What happens if you use the wrong fluid?

[akira]

I am posting this here even though the tranny is not g.m (sorry, but people on other forums are REALLY dumb) In my daily beater (until I replace the motor in my S-15) it uses ATF+3, I accidently poured some synthetic tranny oil in it and now it doesn't work too well! I have to let it warm up for like 5 min before it will catch and then I have to shift it manually (3spd auto). I only added 1/3 litre to the trans and I also just swapped the motor. Anybody have a clue??? Can I just drain the fluid and add conditioner?

[Cliff8928]

You should be able to find some friction modifier to make the Dexron III/Mercon fluid compatible with ATF+3


Cliff Scott
89 BerettaGT
89 Volvo740

[Streetrodder83]

You'll have todrain out what's in there, including what's in the torque converter. Which'll invlove more than likely droping the trans. Then filling it up with the ATF+3. Hopefully that fixes it,if it doesn't you may be looking at a rebuild of your transmission, to replace the friction discs,and bands.

[akira]

I dumped in some addative and I am going to drain as much as possible and install a new filter and top up with new fluid. If that doesn't work these trannys are only $55 cdn at the scrap yard so I'd just install a new unit since it costs like $40 just for the fluid. Thanks guys

[JayBear]

Most of syntheticss work for ATF+3, like mobil, amsoil, valvoline. If you mix synthetic and regular then you get your own syn-blend.

[akira]

I used MOBIL 1 and trust me it was UGLY what happened. I dropped the trans pan plus the diff cover and removed about 5-5.5 liters. There was a huge amount of sludge from the bands slipping. I used some brake cleaner to blow out the valvebody where I could, carbon and sludge poured out of it. So I threw in a new filter and added more trans conditioner and filled with ATF+3 and it shifts almost perfect. I am going to do it again except I will drop the entire valvebody and blow it out. But It works pretty awesome (85%) for now

[geoffinbc]

So what you did was put convertional gear oil (manual transmission fluid) in your automatic tranny and not auto tranny fluid?

You will need to have it flushed out then.

[JayBear]

There is mobil 1 synthetic trans fluid.