Hey guy so heres the deal. My speedometer and odometer were not working and a mechanic buddy of mine told me it was most likely the speedo cable. So I went to the store and picked up a replacement, however when I pulled the dash apart I didn't see anywhere for a cable. So I went to the fuse box and it turns out one of them was bad so I replaced it and everything was good. SYMPTOMS START HERE! Except now the needle doesn't move smoothly, it will come up to 20 and sit there for a few seconds and then it will jump to 35 and it won't come down until I am stopped and then it will jump down in a similar manner. I did take the needle off and I removed the speedometer and odometer assembly so I could clean everything before putting it all back in my truck. Any help would be greatly appreciated.

 

that is similar to my speedometer failure, but i am getting an error code of p0500 (vss, speed curcuit failure) as well. mine is not the vss(tailshaft mount on mine) so now i will be looking into wiring, but it could be the speedo itself. is your Odo still working too? any ABS issues?

 

I haven't checked the codes yet and my odo is working and the ABS light has been on since I got the truck because the back axle swap. Let me know what you find out.

 

So I figured out what went wrong, I put the needle on to far and it was catching on the cluster so when I put it back on I only as much as it needed to stay on.

 

well i am glad you got yours taken care of.
but that's not possible on mine, it bottoms out on the stud before it could hit the gauge face or anything else. i pulled an instrument cluster from a truck in the scrapyard and still have the same problem, so now its down to wiring or the ECM itself. my speedo sits at 0 with the truck off, at startup it goes to about 20 mph. when the truck is in motion it may creep up to 35 mph, no matter how fast i am travelling. i have replaced the speed sensor twice, tested with the scrapyard cluster and need to test the wires next but i need a second person to help me there. if the wires from ECM to VSS test good then i need to find the wires to the cluster itself, if those are good, then its time for a new ECM.