Can a Transmission Cooler be Used to Bypass the Factory Cooler on a 2007 Hummer H3

Question:

My son has a 2007 h3 hummer with auto trans. I am installing a new radiator and have heard that some of the replacement radiators have been having trouble with the trans fluid and anti freeze leaking together in the radiator. So I thought I could just not use the radiator for trans cooling and install a trans cooler that was not hooked into the radiator. Am I on track or not? Dont want to hurt his trans. He does not own a trailer.

asked by: Tpm P

Expert Reply:

It is usually the other way around with factory transmissions coolers in radiators. By that I mean that normally you see a problem with the factory coolers, not the aftermarket replacements. It is possible to bypass the factory cooler in the radiator by blocking off the input/output locations for the transmission cooler on the radiator.

You would then need to mount the largest possible cooler that you can get to fit or install a remote cooler with its own fan. The Series 9000 Plate-Fin Transmission Cooler # D13614 would be a good choice. It is not the largest but it is very efficient and would work well. It measures 11 inches across and 11-3/8 inches tall and it is 1-1/4 inches deep. I have included a link to a video review for you.

For a cooler with its own fan the most popular option is # D13960. With this type of set up the cooler will always receive the maximum air flow.

I have included some links to FAQs on transmission coolers for you.

expert reply by: Michael H