I have a 1971 F100. The speedometer head works very nice UNLESS you push in on the rotating shaft that the cable drives. It then contacts the drum on the back of the needle shaft and pushes it until the step on the needle shaft contacts the needle shaft bushing. The speedomter either does not move or the needle comes up and gets stuck at a low MPH and will neither increase or decrease. Then I stop, needle stays at said MPH, grab speedo cable behind gauge cluster, gently pull out and needle drops right down. I replicated this with the speedo head on the bench. You might think I could just leave the cable a bit loose, but the inner cable seems to work its way up and in the speedo head until it binds it again.

Any one have any similar experience or thoughts? I thought I found a post about a "slipping sleeeve" that alowed this to happen and it refered to a "fix" but said to search "speedo fix" and I am having no luck finding anything,. I cannot even find that post anymore. I am thinking about trying to p[ut some washers between the 2 pieces of the speedo head that are held together with 3 bolts and aligned by a Nub in the "4th bolt" position. I just need something to hold that rotating mechanism that the cable turns and the needle drum apart from each other.

Thanks for any thoughts or advice.