Bought a used Durango last week, and broke it in pulling a trailer in the mountains. It had some noise in the rear differential, so I know it would need gears soon, but didn't think about overheating it. So I was purring along with the cruise on 72, enjoying the power of that 360.
The transmission temp light came on, and I pulled over to check things out, and the rear Diff was really cooking. Didn't see any signs of the tranny overheating.
Just before the transmission temp light came on, the ABS and speedometer went crazy. I have now figured out that it must have fried the speed sensor located on top of the Differential.

So my question is, does the Trans Temp light also monitor the rear differential, or did I overheat the tranny. I was pulling about 3,000 pounds, and it has an aftermarket tranny cooler.

thanks

 

there is no temperature sensor in either of the differentials on these trucks so you must have overheated the trans, but 3k lbs is not a whole lot for these trucks but it might be time for a fluid/filter change on the transmission

and if you are hearing noise in the rear differential i would suggest getting that looked at, if you have an LSD it could be gone and you could have pieces of clutch packs floating around in there chewing up the gears, it should be looked at ASAP, and you have a bad speed sensor, either the one on the rear differential or the one on the transmission, just replace them both as they tend to go relatively close to each other

 

+1 sharp!

 

Thats my thoughts, really not a lot of weight for this vehicle.

 

This sounds like a axle failure causing the trany to overheat, this is not a transmission issue because of hauling too much weight!