Tranny oil cooler

[x2xtreme360]

OK, maybe I'm not thinking this through logically, since it seems that no one has ever done this...

But why, since the VR4's have an oil cooler and don't have auto trannies, don't just get an auto radiator and run the engine oil through the tranny cooler in the radiator? I mean, trannies can build up a ton of pressure, so it's not like the tank wouldn't be able to handle oil pressure.

Is this just retarded of me to think? It seems completely logical and it would cut out the need for an external cooler.

[Hans@GZP]

Because coolant is at 200 degrees and you don't want your oil that hot. 150-180 would be oil temps. You would be heating your oil by running it through the radiator.

[x2xtreme360]

But tranny fluid rarely gets above 180, so if your theory is correct, why do people run tranny fluid into the radiator?

I guess maybe under hard driving the tranny fluid gets a lot hotter than that?

[stealthee]

On hot days I have seen the trans fluid at 212 in my Grand Prix.

[RealMcCoy]

There are meny vehicles out there with oil/coolant heat exchangers... You see it most often in trucks, but quite a few Japanese cars have them as well.

The issue I see with doing what you suggest is the physical size of a trans cooler. The lines are just too small.

And FYI, while an auto can make upwards of 300psi mainline pressure under certain conditions, the lube circuit is regulated to a very low pressure. (usually under 40psi)