I have a 1994 F350, 7.3 Diesel with E40D. I had the transmission overhauled about 30K miles ago. Now the transmission shifts roughly, jerks as you accelerate and sometimes when you de-cel. Drives normally at a higher speed. I also do not have speedometer and odometer not working. I checked the fuse at the fuse box, fuse is not broken. I talked to a mechanic who told me it could be a speed sensor, located on the rear axle housing. Is there a way to check the sensor without purchasing one and finding out that is not the problem. What else could be the problem? Any help is appreciated.

 

It could be the sensor, the wiring or the exciter ring on the diff carrier. Pull the sensor, clean it, check the wiring harness and connector for problems. If you can shine a flashlight into the sensor hole look in, turn the driveshaft and see if there are any bent or missing teeth on the exciter. If everything appears to be good re-install the sensor and see if it works. If it doesn't, you may want to pull the diff cover to inspect the exciter ring but that is not likely to be the issue.

 

I clean the sensor and checked the harness. Earlier checked the fuse under the panel in the cab. Nothing is working, but I have not shine a flashlight to check the "exciter ring". Question, Will the sensor cause the speedometer not to work and the odometer not to luminate?

 

THAT is a different symptom. Do you mean that the instrument lighting does not work or do you mean that the LCD odometer display is blank? If the odo were simply not getting a speed signal it would display an error code. If it is not displaying anything, most likely it is either burned out or not getting power. Since you've checked the fuses (there are 2), you need to check for power at the PSOM connector. The light green/yellow wire (#54) should be hot at all times, the white/pink wire (#296) should be hot in run

 

Sorry, I should have been more clear, the instrument panel does light, but the LCD odometer is blank. I will go and check the two wires you pointed out to see if they are hot. Thanks a lot.

 

Sounds like the PSOM is dead. Read this caption & follow the links in it:

 

Sorry I missed this thread, after you check out Steve's collection of info, here are some more pictures I took when I swapped in a junkyard PSOM to my '95.

https://www.supermotors.net/registry/22140/75545

Adrianspeeder

 

Yo, Adrian! Why didn't you do the low fuel light mod, or the oil pressure mod?