bouncing speedometer

My speedo has started bouncing around +-5mph of actual. I searched for a fix and found where someone had fixed it but didn't say how, just a wiring repair. Can anyone detail it for me please'
TIA

What year XJ?

mine bounces too.. an '87...just a lube job? or do they even have a cable anymore? thanks.. sorry to hyjack the thread

If it's an 87-90 it nees to be lubed...91+ there is no speedometer cable.

If it's the 91+ check out the Vehicle Speed Sensor (VSS) on the t-case output. When mine failed it started out with symtoms similar to yours and then progressed to showing 0mph on the freeway or 40mph while in the drive-through.

Surprisingly enough, you can get a replacement speedo cable for less than $10 at Autozone. Lubing a mechanical cable will normally fix the problem, but I just purchased a new one and lubed it real good before installing.

My needle was jumping pretty bad for a while on my '90. When I was doing 35mph, the speedo needle bounced between 30 and 40 mph. I pulled the cluster, unhooked the speedo cable, used some needle nosed pliers and pulled the metal cable out to where it stuck out about 1/2" past the end of the cable end attachment (white plastic part on the end) and re-installed it. For whatever reason, my speedo is now smooth as new. Obviously, this won't help you if you have a '91 or newer but it's worth a try (and free!) if it's older.

It's a 91