Speedo jumping?

[runninfromthelaw]

I got the blazer fired up with the new tub on and the speedo jumps with the rpms.

A few details the drivetrain and frame are from a 88' and the tub with all the wires are from a 90 plus i swapped the 208tc for the 241tc.

With it in park just raising the rpms the speedo jumps?

 

[jollygreengiant]

I got the blazer fired up with the new tub on and the speedo jumps with the rpms.

A few details the drivetrain and frame are from a 88' and the tub with all the wires are from a 90 plus i swapped the 208tc for the 241tc.

With it in park just raising the rpms the speedo jumps?

Mine used to jump going down the road. Turns out that the cable was pinched between the cab and inner fender. I don't see how it could be doing anything while in park.

 

[clandr1]

Mine did that real bad -- turns out the speedo has some rust in it (no idea how) and the gears aren't turning smooth, so it causes my needle to jump while going down the road at certain speeds. Over time it's gotten better, I assume the gears have knocked off some rust since I drive it a lot more than the PO.

Also, the speedo cable broke on the PO and the speedo wasn't even used for probably 6 months or so before I fixed it when I bought it.

 

[Kjunky5]

Oops, read the title wrong. Thought it was some sort of skimpy bathing suit hopscotch.