Packard Forum Index » V-8 (1955-56)

anyone run a aftermarket auto trans,cooler on there twin ultramatic trans, if so what size,thanks

Yes, I have a aftermarket cooler in front of the radiator and after an unfortunate incident it is now in series with the factory cooler. The reason for that is that, with the car essentially motionless in traffic for more than a hour on a blistering hot day (over 100 deg), the minimal air flow from the fan with the engine at idle was inadequate to handle the heat generated by the converter with the air cooler alone and the trans was damaged.

Owen- Sorry to hear about your experience but would like to know how you incorporated the factory cooler with the aftermarket unit.
I opted to mount an aftermarket cooler for an SUV in front of the radiator but maintain the original cooler without connection to the trans.
I have used the aftermarket cooler on highperformance applications without problem but those cars used aluminum radiators and electric fans which may pull more air than the stock Packard fan.
Do you think the factory cooler would have protected the trans under the same conditions?
RJR

I've used an air-to-air trans cooler mounted in front of the radiator since the early 2000s. I not only disconnected the stock T-U cooler, but removed it entirely and used a replacement flex hose to connect the radiator and water pump inlet. I cut and connected the trans lines to the new cooler.

The T-U works perfectly. It gets to 115F here in Southern Nevada in the Summer.

I'll try and take a picture tomorrow and post it. Maybe I can find the original receipt buried somewhere in my files.

Craig

RJR, as it's now configured the two coolers are in series and the air-to-air cooler is first, followed by the factory cooler. The car is occasionally driven in the winter in sub-freezing temperatures and my thought was that if the air-to-air cooler was second, the fluid might not reach a proper operating temperature. The car has accumulated about 15,000 miles now in this configuration and the transmission has performed flawlessly.

Yes, I think the factory cooler would have prevented the problem. My caravan companion on the drive had an identical '56 Caribbean; both of us watched our engine temperature climb, nearly pinning the guage, wondering who would first get vapor lock or boil over - but neither car did and we were impressed with the V8s resistance to vapor lock and overheating. He did not suffer any transmission problems.