I have a 72 chevelle malibu conv with only 48k orig.It has factory cruise.The speedo needle bounces at 10mph no matter what speed.How do I determine if it is a speedo or a Cruise regulator problem.It is a sweep style speedo.I hate to take the dash out unnecessarily in this clean survivor.Any help is appreciated.
Thanks,Russell

Sounds like the cable needs to be lubed. Unhook it at the back of the speedo, pull out the cable and lube it up with light grease.

Dave

i unhooked it from the regulator and lube toward the speedo.It turns freely.