So for starters I have a 96 f150, 4WDR, 5.0. I've been having issues with the speedometer for a while now, at first it just kind of jumped around and then would either stop working all together, or it would work... Very sporadic. Then it full on stopped working, but the tach still worked for a while, then the tach did the same thing, worked sporadically and then quit all together, so I switched out the PSOM and I believe the one I got from the wrecker was in worse shape then my own because then none of my gauges worked, no odometer reading, Nothing. So I put my old PSOM back in.... About a year later I decided to tempt it again, so I went to the wrecker and got a full cluster, swapped it out and now the tach works, but still no speedo! I put in a new speed sensor on the rear diff today and still nothing.... I have no idea what to do, my ABS light is on and O/D light flashes, but O/D still works. And it definitly shifts tough now.

One other thing I was curious about is that the speed sensor I picked up from the parts store, was a bit different than the one I pulled out, on the new one the part that inserts into the diff itself, was plastic with grooves in it, and the original one was metal and no grooves.... If anyone has any clue Id hugely appreciate it, I apologize if this post doesn't make sense or adhere to forum guidelines, I'm new to this! Thanks so much!!

 

Bump

 

Check fuses #8 and #18 in the fuse box inside the cab.

 

What does bump mean? And the fuses are good.

 

Were the replacement psom and cluster from a 96 ? Earlier ones don't work in a 96 - the computer system changed from OBD1 to OBD2 in late 95.

 

I believe they were both from a 95, is it weird that the tach would work now? Even with a PSOM from a 95

 

They're modular clusters. The tach from a 95 should work fine. The problem is the 95 PSOM. The electronics in the 95 PSOM are most likely for OBD1 computer control systems. The 96 truck has OBD2.
I would guess that is most likely the problem.
I have read that as far as cluster interchangeability the general rule of thumb would be 92 and 93 / 94 and 95 / and 96 stands alone. Diesel and gas tachs are different.

 

It's also been reported that the last 6 months of 95 won't work with the 94-95 swap as they started redoing the wiring getting ready for the obdii swap.

 

Yeah, that's where all the most likely's come from. The only thing you can be reasonably sure of on a 96 is that a 96 PSOM should match up. The sh** you've gotta know about these trucks to work on them !!!