fastegg

Here's my kick **** transmission cooler. I originally used a 'standard' size cooler whilst still using the coolant radiator cooler. I had an ATF temp gauge which told me the ATF was running at about 85 degrees while driving and 95C (205F) sitting at the lights. I bypassed the coolant radiator and it dropped about 10 degrees... but 85C degrees (185F) was still to hot... I wanted the transmission to never exceed 70C (160F).... So I fitted a B&M Super cooler... Its about 40% bigger and twice as thick as the one I had.... Now the ATF runs about 55C (130F) while driving and 65-70C at the lights....
Sweet... I'm happy with that.... The reason I did this was I asked my friend who had an automatic transmission business if I could make my transmission last literally forever... He said he wasn't sure but to give it it's best shot was to use synthetic ATF, which was overkill for my needs but the best fluid, and the other was to make sure that the transmission never exceeded 70C... never let it get hot.... So it has Nulon full syn ATF and oversize cooler.... Whenever I come back from a drive, I can leave my hand on the cooler.... Woo Hoo....

Stroock639

does the car have a transmission fluid temperature sensor? i got the elm327 obd-ii wifi adaptor so i could get a bit of real time data as well as be able to see any codes should they appear but i didn't remember seeing a PID for transmission fluid temperature, or engine oil temperature for that matter

nice job on the cooler though, now you'll just have to make sure you don't die before the car does

GeorgeNVA

I've been once told that any ATF has its optimal temp range where it performs best. Isn't 70 degrees C too low? I mean fastegg, could you ask your friend if he has any ideas on minimal acceptable atf temp?

fastegg

Hi GeorgeNVA... Well he originally told me to keep the ATF under 70C. Now I built and raced road racing bikes for 20 years and back in the days when we were running big aircooled 4 strokes, heat was always our biggest enemy. I saw countless dozens of motors expire due to excessive temperatures... My point is I never ever saw or heard of an engine or transmission fail because it was running too cool.
He did saw however to keep an eye on it when winter comes as its just the beginning of Autumn now. Winter will get many weeks under 10C, some days near freezing. Its probably not good sending refrigerated ATF back to the transmission.
PS: While I was at it I replaced the stock power steering cooler pipe with a proper cooler. (photo below) $35 brand new on ebay including postage. Before, the power steering reservoir got so hot you couldn't touch it and when continuous 'sport driving' the power steering reservoir got REALLY HOT.... Now, it never gets hot enough that I can't keep my hand on it.

GeorgeNVA

The power steering cooler is a nice mod indeed, though the only way I could feel its effectiveness is by touching the reservoir. The steering efficiency seems to be the same as without one.

Now regarding the frozen ATF. It's recommended to heat the engine prior to pushing it hardly. I believe it's the same story with the transmission and its fluid.

fastegg

Agreed.. But I never 'push' the transmission anyway... But I figure keeping all the oils COOL will make everything last longer...
I have one of those hand held laser red dot temperature reader thingys. The hottest the power steering reservoir gets is about 60C and drops to about 40C when driving... And I fitted a temp sensor in the ATF line..