So, this started happening a number of years ago while I was still driving my car. It first happened progressively. I would just be cruising at 30 or so and the speedo would read fine, then it would jump waay past 100. Now it always reads too high, it will wrap past 160 in 3rd.

The transmission has been rebuilt since so I figure the drive gear for the speedo cable is good, also when I put it in last the driven gear on the cable was good as well, as in the teeth werent stripped out or anything.

Anyone encountered this before? Could another gear on the guage end of the cable be jacked up or could the speedo itself be bad?

 

Sounds more like the speedo unit itself is wearing out. Thats what happened on a old MX3 of mine(93 with cable drive unit), spun around fast enough to break the needle. Put a new speedo unit in from the junk yard was was all good.

 

I thought that may have been the case. My guage bezel is so jacked up and half the screw mounts are broken. Looks like I'll just have to replace all that at the same time. Thanks for the info.