RE: 99 durrango speedometer dont work
The two are different. I know cause both broke on me within a month! The rear sensor is the one that usually makes the ABS light come on and futzes up the speedometer. The one on the tranny, in my case, made the tranny shift really late, and lit up the Check Engine light.
So, you need to change the rear sensor, on top of the diff and YES it is a different sensor. Not expensive though.