Transmission cooler

[Indycars]

I started out with the finned aluminum cylinder mounted parallel with the frame right ahead of my tranny crossmember. I have a 3000 stall converter and idle at 800-900. I got curious about tranny temperature and installed a temp gauge with the sender in the tranny pan. I found that tranny temp was staying in the high side of the desirable range (using TCI's chart http://www.tciauto.com/tc/trans-life-expectancy) most of the time, but on warmer days in stop and go traffic it was getting into the 250-260 range.

I wasn't comfortable with that, so changed out to this cooler set-up... http://www.summitracing.com/parts/der-15950. I have the fan on a relay and toggle switch rather than using the temp switch, as I wanted to have more control of when the fan is on. It is mounted on the back of the body just above the pinion on my Jag pumpkin. Work's great! I very rarely have to turn on the fan, which I do when the temp approaches 200.

Lee, what kind of temps do you see on the highway at 75 mph and an ambient
of 95°F plus, without the torque converter locked up or are you running without a lockup TC?
What trans are you running?

[Lee in KC]

Rick, the only time I see tranny temps above 180 is in stop and go traffic in the city on hot days... 90* plus. On the highway I never see more than 180. I have a Turbo 350 with a 3000 stall non-lockup converter.

[Indycars]

Interesting, I have the most trouble when I'm cruising at 75 mph with the torque converter
unlocked. When I do lockup the TC, then the temp can drop by 30°F. Maybe there is a
higher load in the torque converter with the .67 4th gear.