Hi

[Kalums]

Originally Posted by Steeveedee

I don't think that it makes a lot of difference, though I've seen claims that the trans warms up faster because the coolant is warming the fluid first, before going to the extra cooler in cold weather. I'm not convinced of that. The trans and engine would be coming up to temp in a somewhat parallel time frame. Maybe someone with a factory trans cooler in addition to the radiator intercooler can chime in.

So I actually ended up talking to a local transmission shop and the guy whips out a Hayden manual that said it is supposed to be hooked up to the return line "so the cooling effect" is essentially doubled... So pressurised side (out from trans-bottom hard line) goes into the radiator( unless you bypass radiator) then tap the top line ( return line, out of the top radiator) to the bottom of external cooler, then top of external cooler to return line - top line in the transmission. Ended up getting a new 9x13" cooler( way more than I probably need but it was $40 because the package had water damage, mine had a crack in the neck of the bottom hose when he pressurised it. But take this all with a grain of salt because I live in the desert... Where "cold" is NOT a thing, LOL.