Every since I installed my trans cooler my dipstick readings seem to be off. When the car is cold sometimes fluid is alittle above the hot mark on the stick. Then sometimes when the car is hot and I check the fluid it is barely in the cold marks. I have a 4L60E out of an Trans AM and I have my oil cooler installed in series with the radiator.

Did this happen to anyone else? Is it normal?

I don't want to hurt my trans so if someone could help me out that would be great.

Thanks in advance,
Jay

My dad has always told me to check the transmisison fluid when its at operating temperature. Nobody has ever told me different, or the same, so i'd rather the trans have enough fluid when it's running than sitting. I think when it runs, the fluid gets sucked around and pressurized into lines which leaves a little less in the pan.

Check it when its at normal operation temp. In park or neutral. Fill it up to the HOT mark on the dipstick.

It should not make a bit of difference, once it is filled up......It will take a little more depending on the size of your cooler....

check it when the motor is running in park, typically after a little drive to warm it up.

I checked it in park @ normal operating temp and it still read low. So I'm guessing I need to add some fluid. However, if I do that when its cold it will be way pass the hot mark.

Is the hot mark the only one I should be concerned with?

I just don't want to hurt my trans.

Thanks,
Jay