The Debate about Overfilling a transmission? Which is true?
 

Ok whats the story? I have hear many people online say not to do it, it will mess up your trans. The other half says overfilling does not harm your transmission. Which is it?? I currently do not currently have an overfilled trans, however I would like to know which is the right answer. Expecially since I sometime have had my trans over filled.

Don't do it, but don't do it minimal. Like whenever I fill up my transmission fluid, and engine oil, i always fill it up to 3/4 full on the cross hatched area. That way it won't be low, and not overfilled. It's the best, IMO

When/why is your trans overfilled?


-justin

Trans was overfilled a while ago. Hasn't been for a while. I was just wondering just for the sake of having the right information which is right.

i would rather have more fluid than less, if that is what it came down to

some trannys will just puke it out if its REALLY high.. not sure about the 4T6* series

Yep yep, I will agree with that. I think the tranny could handle an extra quart, but past that I think toast is right in that it would just puke it out. If it has nowhere else to go, ya know? Where is it supposed to go?


-justin

Over filling the trans can cause the trans fluid to come out and cause a fire or foam causing mass destruction of the trans.... A little bit over will not harm anything... I am usually at or near the top of the crosshatched area, But you have to keep in mind that trans fluid will expand as it heats up, so when you check the trans hot it will be a bit higher than it was cool... Mine is usually full on the cross hatched area...

__________________
Best Car Insurance | Auto Protection Today | FREE Trade-In Quote

While on the topic sorta...what about engine oil? How full is too full?

Someone I know with an oil and filter change does 4 quarts.

Someone else I know (maybe its me :oops: ) does 5 quarts.

Manual says 4, but up to one more with filter change.

err.. LE/SE is 4, SSE is 5.5 [for 89 taht is]. Makes no sense.. but as long as when the engine has been driven [10 mi is probably all needed], then cooled down, and it's in the mid of crosshated its good. Doesn't matter about quantity, more about level. Sometimes my car only wants 3.5 quarts, sometimes it wasts 5. Just gotta conform.


-justin

The car wants four....after you put five in, because the filter is empty when you install it, and most filters will hold a qt alone.

If you were to over fill your trans, amongst what Don had mentioned about your trans pissing it out all over the place, and prolly burning your car to the ground.....You could blow out internal o-rings and possibly external seals and cause a premature trans failure.