I need your help and direction. My 2001 F150 (5.4V8) with 150k miles having some issue with the tranny. I have seen a few threads, but nothing exact to my scenario.

Yesterday, my Speedomoter quit working, the Odometer (when it lights up) is showing "-----------" and the OD button on my shiftier is flashing. I limped the truck home as it was shifting poorly or not shifting at all.

I jumped on the web and saw several threads suggest it is the OSS or RSS sensor that connects to the rear driveshaft. So I drove down to my local parts store and replaced the $15 part.

Not only is the issue not fixed, but the "Check Engine" light came on. My local parts store pulled 2 codes. P0722 Output Speed Sensor- NO SENSOR, and P0720 Output Speed Sensor Circuit. I checked the old OSS and my ohm meter did register resistance, so this is not the issue. I am hoping for best, but praying for the worst (Tranny Replacement).

Has anyone had this same issue and if so, what was your fix?

Thanks,
Bill

 

Have you checked the harness going into the trans for physical damage? Checked all your fuses?

 

It is very, very unlikely that the problem is in the trans.

The sensor that sets that code is the one on the top of the transmission at the rear of the trans. Is that the one you checked? If so, the problem is almost certainly in the wiring between the PCM and the sensor. Sometimes it is a lot easier to replace the wire instead of trying to find the problem.

 

yes I too have been having a bad time with my transmission in my 1995 ford f-150 xl 4x4 5.0 engine. Speedometer, odometer both don't work o/d flashes engine light on . When put into gear or driving it shifts hard had the speed sensor replaced to no avail. I've been told not to drive it cause it will mess up the tranny. have read up on all the cause and there are so many i don't know where to start. some of the cause is the speed sensor which I did, check the fuses which I did short in the wires which I did not and the rest of the suggestions I did not one of which a lot of people seem to lean to is the instrument cluster on the dash. I feel stuck not knowing what to do and would appreciate some advice

 

I did some more checking. My tranny stick was measuring some, but not much tranny fluid. None while engine was one. I looked at tranny pan and saw where some had leaked. I followed the tranny fluid to a hole @ the size of a nickel. then tucked on a lip on top of tranny was a sensor. Not sure how it stayed on the vehicle. The wire it attached to was right there too. I reconnected, filed up tranny fluid, and had Advance wipe away check engine codes. I drove through some brush/tree limbs. One of them must have got stuck and ripped the sensor out.

 

My advice it to take it to someone that knows how to find and fix a wiring issue. If the new speed sensor didn't fix it, then the problem is most likely in the wiring.

 

Thank you for the advice . Kind of hard getting a mind set into a transmission problem being electrical but when you think about it being controlled electronically it makes more sense. Will let you know more when I find out. Rich