1993 ford f150 4.9 2x4 Im having an issue of which I cannot find the answer to. When I am going 3mph my Speedo peggs out. (Over mock one) I believe I have a have a beggining of year truck because I only have the speed sensor on the rear diff. I have a port for a output shaft speed sensor on the tail housing but its blocked off with a block plateAny help would be appreciated.

 

First thing I would suggest is to make sure the wiring to the speed sensor on top of the differential looks ok. If it does than you can pull the sensor itself - it is just one bolt holding it in. Might take a little leverage with a screwdriver to get it unstuck but it should pop right out. Give it a good cleaning. If that solves your problem then its probably a good idea to change your diff oil.

I'll let someone else comment on the possible problem with the speed sensor not being there on your transmission, which might end up being the problem - would only be speculating there.

 

Click this & read the caption:


(phone app link)

Test the PSOM as described, and find out what software revision it is. If it's very low, consider snagging a later one from a JY. They're not expensive or difficult to change. This album's captions explain how to rebuild the instrument cluster:


(phone app link)

 

Thank you Steve 83. This was very helpful and I will look into it.