My GF called and said this morning that her Durango would not upshift this morning when she would hit 3500RPMs doing 55mph. She said the truck was loud but not grinding or hesitating. I did some research but couldnt find anything. Any suggestions of where to start?

 

Ask her if she accidentally had the shift lever in the wrong position. Honestly, until you can experience the issue first hand and not second hand information, there is not much of anything we can do for you.

 

I would first make sure that the rotating **** is set to AWD AUTO and not LOW RANGE.

What did the EVIC display (under the speedometer) show? Did it show the trans in D when the issue happened or in a different gear number (i.e., 3 or 4). The shift lever may have been inadvertently bumped towards the left (driver) which would have downshifted from D to a lower gear.

You could also manually upshift from first through all the gears (1 through D) when starting from a full stop to see if the trans is working fine manually, and then do the same by starting in D.

 

I am going to drive it when I get home tonight and see whats up. I understand what you mean about second hand info. So the speed sensors tend to go bad in these trannys? From what I could find it seems to point to that if it wasnt operator error. If so, is it an easy fix?

 

So i took it out and could not get it to duplicate the issue and shifting manually went fine. So she may have knocked the shifter over leaving it in 3rd or 4th. I did however find out that the water pump was leaking and spraying coolant everywhere. So time to replace that.