I have had a couple times when my Bronco was shifting rough and the speedo needle jumping all over the place, also the ABS light is on and the overdrive light was flashing. The first time it happened I disconnected the battery and it went away. Yesterday it was really bad, I disconnected the battery and the problem was still there. Today I checked all the fuses, disconnected the trailer brake controller I installed, and removed and cleaned the sensor on the differential. All seems to be good now. Fuses were ok. Don't know if the abs light is on because I pulled the bulb out months ago .

When I pulled the sensor off the differential it was covered in some metal shavings and the oil was pretty black. I am going to change the diff. oil. Any advice on what oil to put back, gaskets, etc.?

I am worried about the metal shavings. I would like to see inside the diff. at least if nothing else to see what I am up against. Not interested in putting on a new diff. right now! but will if I have to.

Oh yeah, the problems seem to happen right after I pulled a trailer, the first time I pulled an overloaded enclosed trailer an hour or so and the second time my 28' travel trailer just up to get inspected and a few miles down the interstate.

 

change that sensor first, if the problem continues the next area i would focus on is the ABS control module that is located under the wiper fluid tank. Now this module was the source of my issues that sound just like yours. also this module tends to be year/model specific so in your case do some wrecking yard searching before buying a new one.

 

Pull the cover and see what it looks like in there. No gasket is required on the cover, just RTV. If you have the limited slip axle (code H9 on the door tag) use either standard gear oil plus 4 oz. of friction modifier or a synthetic which has it already in there.