Can too much transmission fluid hurt the shifting of the transmission???
 

I checked the dip stick and it's way off from where it's suppose to be. When I got a tranny cooler I added half a quart, so can too much tranny fluid affect the shifting?

I doubt it, it just sits
 

I doubt it, it just sits around and lubes, not like it's exerting pressure or it'd shoot out the fill hole.

I checked the dipstick and
 

I checked the dipstick and it's 1 inch higher than H, which is a little more than should be in there. I'm afraid to take out some fluid because I have a tranny cooler and it won't cool the fluid.

I've always heard that
 

I've always heard that aoutmatic ransmissions were kind of fussy about fluid levels. If you had some way of drawing a little out through the filler pipe it may help you. I had to do this on my Durango one time. It had a factory installed tranny cooler and it was showing overfull on the dipstick.

Thanks for the advice Larry,
 

Thanks for the advice Larry, anyone else have same opinion as Larry?

a quick google search turns
 

a quick google search turns up no shortage of pages warning against overfilling. to be safe, i'd remove any excess fluid.

Thanks, I'm going to remove
 

Thanks, I'm going to remove the excess fluid. I think there is 0.5-1 quart too much.

If it's anything like oil...
 

If it's anything like engine oil, if you overfill it, it tends to become a foam becuase of the excessive movement against moving parts, and essentially renders the oil un-pumpable and won't get to vital parts. I'm thinking that trans fluid is similar, especially when pumping through a cooler. I know it's probably a pain to fill or drain, but I'd recommend getting the level within tolerances.

RH77

I used a hand operated pump
 

I used a hand operated pump that I got from Autozone or someplace like that. It had a hose small enough that fit down inside the transmission dipstick tube. Much easier than taking the pan off and only takes a couple of minutes.

Re: If it's anything like oil...
 

The problem is that I have a tranny cooler so extra fluid is required but I don't know how much is required. So I'm going going to drain it till it touches high. Right now it's way too far from high.