Transmission fluid level

How sensitive is the transmission to the proper level?

I know on the 3rd gen automatic trans supposed to get a trickle at 105-125 while running in park.

How bad would it be if overfilled by 1/2 - 1 quart?

 

Interested in an "official" answer but do know that sometimes too much fluid causes an over-pressure status that can blow out seals.

I have no idea if it does that with our transmissions but recommend making sure before adding extra fluid.

 

Why overfill it at all? Just follow the proper procedures and you don’t have to ask the “what if” question.

 

When I dumped old fluid I got about 2 - 2,5 quarts.
I pumped in about 3 quarts after adding a tranny cooler. I did open overfill, albeit when pan temp about 140 to let some out, but being too hot I wanted to wait until I could do when cooler.

I did work when visiting friend. Generally I live in my small RV so having a place to work on truck is difficult.

 

Ah. What’s the volume the additional cooler holds? You added .5 - 1 extra quarts but you also added additional capacity, so maybe you’re not as overfilled as you thought. I guess it depends on the order of operations for the drain and refill and the additional cooler install, and whether you lost any fluid doing the install.

 

assuming your engine is running when you are checking the fluid ?
Overfilling causes foaming of the fluid .
Some guys skip the engine running step when they have the drain plug removed .
There are additives in Your transmission fluid that help to prevent foaming .
Its not uncommon to add a little more fluid within reason in trucks with 4x4 to compensate for steep hills and tight corners . This prevents the transmission pump from cavitation .
There are NO additives in transmission fluid to compensate for a low fluid condition .

https://www.tacomaworld.com/threads...th-pics-for-second-gen-4-liter-trucks.289913/