[bandit77]

My speedometer is not accurate. It hasn't been for a while. My guess is that it's about 5-10 MPH below the true speed. Any ideas how to fix? I don't know if this matters but the transmission was rebuilt in '97.

Thanks,Tom.

'66 Mustang (I-6, Sprint 200, C-4 Auto, Conv)

 

[gjz30075]

The easiest and cheapest way is to change the driven gear on the end of the speedo cable. There's a clamp that holds the end of the speedo cable into the trans. Pull the clamp off, then pull the cable out. There will be a gear on the end of it. Change this gear to another one with a bit more teeth. Any Mustang vendor or Ford dealer will have one.