Has anyone had their speedometer apart? I took mine out because the needle was bouncing around and the needle would not go back to zero when I stop unless I bang on the dash or back up 5 feet. I got it out and apart very easily. I blew it out with air and lubed it with some WD-40 "dry lube" spray. I also tightened the spring just a smidge so it pulls the needle back to zero better. When I put it back in the truck, now it is 5-7 mph slow. Before I messed with it, it was only 2 mph slow. All of these speed comparisons are with my gps. I am wondering if I over lubricated it, or if tweaking that spring caused this. If this is gear driven in the assembly it would not be able to slip, but I did not expect this to happen.
Anybody else experience this or have any idea/opinion?

 

The spring is used to calibrate the speedo, so that is why it reads low now.
When mine has started bouncing, it was always a problem with the cable.

 

Thank you. I will move the spring back. I did spray some lube into the cable also and my needle did not bounce anymore, it just read slow.
Thanks again.

 

Well after adjusting the calibration spring back a little bit at a time, I now have the speedometer right on or at +1 mph. I figured that is close enough for me, and the best part is that I did not break anything. I am now extremely good at getting the speedo out, apart, and back in! After lubing the cable good, I don't have that needle bounce issue and the needle returns to zero when I stop.