2006 4x4 2500 duramax with 6 speed allison,40,00 miles
yesterday i was towing empty (about 2500 lbs) on small hills nothing big at all about 105 outside i did have the a/c on....when i noticed my tranny temp rise to maybe 225 (normal??) after i parked and unloaded the tralier and desended the hill it went to the normal 175 180 its never done that to me even towing 10thousand pounds...truck is serviced often and not abused.. i have no add ons too. thanks........... what gives?????????

You will likely be at least 100*F over the outside air temp, especially when outside temp is well over 100*F. Think about how hot the pavement/asphalt would be and all that heat is radiating right up under your truck and against your tranny body/fluid sump. If you were going slow or even sitting still idling in that heat, I am not surprised at all.

I have tracked mine towing and empty the past month or so and a rule of thumb I saw elswhere on here of oustide temp + 100*F has held pretty close. For that brief a period of time, you most likely didn't hurt anything. If you are concerned, check you fluid, maybe take off your spin on filter and check smell/look of fluid in filter. If okay, refill spin on and reinstall.

Isn't redline up over 230*F on the guage anyway?? I wouldn't even worry about it unless were at or above redline for a sustained period of time. These trucks/powertrains are designed for this and if 225*F was dangerous for them, you can bet the GM engineers would have set the little red line below that as a safety factor.

when was the last time you changed your spin on?

thanks jfarr your right about that....it was hot and it did cool down right away....thanks...............................


i changed it about 10 thousand ago....not much towing since then too thanks