trans temp when towing

Not a Dodge but my Duramax/Allison hit 228 F on a slow climb up a forest service gravel road hauling a 7,500 lb 5th wheel. Was a little worried but it sounds like newer trannys and fluid can take more heat. Overall it sounds like 240 or 270 (sorry forget) is a bad limit. I also figured the truck will tell you to pull over if it gets too hot.

My Dually Ram 28K combined load. 181 at 90+ outside. Flat land or 6% grades. 170 at 80 and so on. I did a complete fluid exchange to AMZ/OIL ATF and a Mag Hytec deep pan. Mine does run cooler than others I have read about.

FYI leave TH and EB on all the time.

Keep in mind the newest transmissions from all the makes run hotter than the older generations. They don't fluctuate as much when pulling hard however. But having warmer fluid means helps them improve efficiency ever so slightly. Also all the new fluids are full synthetic so they can take hotter temps. Also your PCM will retard power in the unlikely event you did overheat the transmission.

invstr55 wrote:
I have a 2012 Ram 3500 and have a question for those with similar trucks. When towing in the tow/haul mode with the exhaust brake active what is an acceptable transmission temp. My previous truck did not have an exhaust brake and seldom went above 170.

Have you tried here?
http://www.cumminsforum.com/forum/4th-gen-powertrain/

The highest I have seen on my 2011 Chevy diesel/ Allison transmission was last summer in New Mexico, at 106°F outside temperature, was 155°F on the tranny gauge. This was pulling our 31 ft. fifth wheel. When I was pulling Monarch Pass in Colorado, the transmission temperature was about the same with cooler outside temperatures. Climbing the pass, this was using the tow haul and exhaust brake turned on. I didn't check it going down the west side of Monarch though. The cruise control was set at 45mph, so the exhaust brake and Allison working together, held it to within 5mph of the set speed. Should check the tranny temperature when going down hill next time.
Around here on the way to Orlando, a three hour drive, I would expect it to be in the 135/145°F range. Now these are not with the tow haul engaged, but are with the exhaust brake turned on, as I always have it on when towing the trailer.

I have a Chev 2500HD 6.0 gas & pulling a 6000# TT. Trans temp in mine ranged from 150 flat to near 200 while pulling a steep grade in Idaho mts. As a guide think of cars & trucks without an external cooler they utiize the radiator coolant as a cooling medium so they will run 190 - 210 all the time. It would be good to here some more info on this subject.