Should I Replace my Automatic Trans Valve Body?
 

My 1994 Saturn SL automatic has over 300,000 miles and Its a fact it's been 7 years at the bare minimum since the fluid was changed in the transmision. The fluid is black and bubbly for years now as far back as when I first checked it when it was not mine. I honestly would assume its been over 10 years, 210,000 miles since a fluid change. My Saturn has the reverse issue where it slams into reverse after working the gas pedal to get it to shift. I want to replace the valve body and fluid but there's that risk of damage from replacing the fluid of an automatic transmission that's been neglected. Would it be a safe thing to replace the valve body and fluid without any harm?

I don't know enough about transmissions to give you an honest answer. I did that with a frigging Mitsubishi I had a couple of years ago and the damn thing never shifted right afterward. I even changed the valve body twice, but that didn't help. I think the new fluid just finished off bad clutch paks. I should have left it alone. Finally sold it for scrap price.

Then I will just wait until I do a complete transmission rebuild.

Alpha has mentioned that if you have a neglected tranny , don't change the fluid

I already knew that one. Was just unsure if the harm of it was with the valve body, the gears, or both. Now I know it's both, so I will just wait until I have the chance to rebuild.

It might not be a bad valve body, just a bad shift solenoid.

My daughters 2001 started to do the hard shifting into reverse and I swapped around 2 solenoids and it worked just fine after that.

The thing is I cannot do anything that would require more fluid to be added to the transmission because it runs the risk of damaging a neglected trans.

only drive 5 spds.

Guys that have done this (opened up valve bodies)
----how much fluid did you lose/have to replenish when done?

Don't worry about the tranny until you see if the engine needs to be rebuilt.

Already know that the trans comes after an engine overhaul.