When towing, what is the highest trans temperature you can reach before causing damage? In an aftermarket transmission.

Also, after a hot run is the fluid ruined or does it rebound to normal operating conditions once it cools down?

 

i would say normal operating conditions would be around 150. towing a little warmer.anything around 180 and higher stay away from

 

Temperatures depend on where you are measuring them.

Pressure port = BAD location, you will see high temps, but it will rise so slow that you can't back out or shut down before damage is done.

My preferred locations:
Temp sensor in Pan: gives you a buffered temp reading, and gives you an idea when things are getting bad, with enough time to prevent damage.

HOT trans cooler line: This line comes right off the torque converter. If you don't know what you are seeing, it may show too hot, too fast and you'll over react. However, it gives you a fast idea of where your temps are heading, if you are slipping too much or heading for a problem.

Personally, I use both. Sitting at a stop light, the TC will spike up to 190-200, while the pan still reads 170-180. Freeway, TC locked up, and running for 10-20 miles or more, the pan temp will equal the TC temp.

HTH

Tony

 

as long as you don't see the temps get to boiling... you're ok. Especially in a built trans the temps run higher. Mine runs between 160F and 190F. At the track it can sometimes get to 200F but, that's rare and really depends on the outside temp.

 

So 210* is way too hot when towing?

My sender is in the pan.

 

That sure is pushing it. I run 220psi of line pressure and don't get that hot. I'd have it look at if I were you.

Unless you had the trans built for towing... performance trans really aren't meant for towing

 

Not really, its plenty but under what conditions? If its towing around town or where the TC is not locked all the time its quite normal and acceptable.

Is it running 210 at 70 mph on the flat with the TC locked? A little high but not too bad. How weight are you towing?

ATF+4 is rated ar 320 degrees temp for a lot longer than any of us will ever see it. In comparison your temp is not high enough to worry about. If you see these temps as a norm just change the fluid every 25-30k and you should be ok.

 

Mine will get to about 220° when driving around town expecially if I am getting into the throttle some. If I'm just cruising on the highway it normally runs about 170°. This is a stock trans with the sender in the hot line.

210° in the pan is pretty toasty.

 

I did get up to 210* while towing up hill at about 25-30mph. I did pull over to let it cool down before proceding.

The trailer was about 13000lbs.

Would an electric fan in addition to the stock fan help with cooling? Where would it mount? In front of the radiator/intercooler/AC cooler?

 

Nope, that was purely the TC being in fluid coupling. If thats all it got too with that weight you have no problems. I wouldn't even have slowed down for that temp.

Manual second and lock the converter and should not see close to that temp. Not sure whether your truck will do it but my 05 will lockup in 2nd gear or I use a switch to lock it.