Transmission Oil Cooler Questions

[JWL1940]

My '63 R1 with the automatic transmission has an after market oil cooler mounted in front of the radiator and ac condenser. The connection is such that the lines go directly to the after market cooler and are no longer routed through the radiator tank heat exchanger. I believe this was done to try and relieve heat load in the radiator. The problem with this fix is that when the car is not moving there is no air flow through the cooler and no fluid cooling. Is this a valid concern?

I am considering routing the cooler lines to have the coolers in series with the fluid first being routed through the after market unit then through the radiator and then back to the transmission. This would allow the oil to be cooled before going through the radiator, lessening the heat load and still allowing for heat exchange when the car is not moving. Concern I have about this would be the pressure drop. Anyone out there with experience doing who can offer advice on this plan?

I'm new to Avanti and expect I'll be back from time to time seeking advice from those in the know. Thanks.

(o{}o)

[silverstude]

The usual motive for doing this is that the cooler in the radiator cooling coil had a leak and was bypassed. Regarding the cooling capacity, the radiator would always be at 180+ and would keep the trans fluid at radiator temp, which may not be the best situation. Don't forget the Stude engines develop a sludge problem area in the rear water jacket over the years and the temps go up..

Moving the cooling to an airstream depends on the cooling capacity of the device. If one of those Hayden types, they are fairly good at their job, using the engine fan to pull air through it before the radiator. IMO, it would keep the trans fluid temp below engine temp, even when at a standstill.

[JWL1940]

Thank you, silverstude. You gave me some more things to consider. I have owned a late model Tacoma and Ranger pickup that had a transmission cooler mounted in front of the radiator rather than a heat exchanger in the radiator.

[Gunslinger]

You might still have the transmission cooling within the radiator as well. Trucks with a factory tow package usually have the added auxiliary transmission cooler mounted in front of the radiator along with the internal radiator cooler.

Any vehicle that tows any kind of weight behind it needs an auxiliary cooler...whether installed by the factory or aftermarket. I used to work at an RV center thirty years ago and more than once we would see someone have their vehicle towed in because they either refused to spend the money or felt an auxiliary cooler was unnecessary. They would end up with a burned up transmission some distance from home or their destination...not a good way to enjoy a vacation.

[mfg]

I'd leave it just the way you have it....I set up my own everyday driver '83 Avanti that way 22 years ago, and the transmission is still going strong!

I've always been an advocate of not pumping hot transmission fluid into an already hot radiator!

[JWL1940]

I mentioned doing a serial cooler line routiing. Plumb the transmission output cooler line to the auxillary cooler then instead of going back to the transmission route the return line through the radiator (if there are no leaks) then back to the transmission. Probably leave it as is, but interested in comments on the serial routing. Thanks.

[dynolou2]

The correct way to route fluid cooling would be thru the radiator then thru the aftermarket cooler then back to trans. Front line at the trans is pressure out rear line is the return. The radiator may have been bypassed because of a leak, is it possible to ask the former owner? Lou Cote

[JWL1940]

Lou, good suggestions. I was thinking of going into the auxillary cooler first to get rid of some of the heat before going to the radiator. I have had conversations with the previous owners (wife and husband), and they have been most helpful and cooperative in answering my questions about the car. I will ask them about the modification. Thanks - John