Speedometer jumping, and inaccurate
So there will be trany fluid where the cable attaches on a 4 speed?
And this twitchiness can hurt the speedo head? Would I be better off detaching it til I have time to sort this out?
Sure, there's fluid pretty nearby-- after all, the plastic pinion gear that drives the speedometer cable is inside the transmission, meshes with a spiral gear cut on the output shaft. That entire gear mesh is lubricated by trans fluid. Concentric seals near the pinion gear keep fluid from exiting the transmission: one keeps it from dribbling on the ground, one keeps it from heading up the speedo cable sheath.
The way I figure it, the tiny little bearings holding the speedo needle were designed for however many million cycles of 0-60-0. No point in arriving at that wear point prematurely. And yes, I've bought two cars with speedo heads that had failed in such a catastrophic way that the needle had totally fallen out, sitting at the bottom of the instrument cluster, and the little spring was stretched out and wrapped around the mechanism a dozen times. (Perhaps a dirty/gummy/worn mechanism grabbed the needle and played a game of tetherball? That brief event would have been pretty exciting to watch.) The speedo repair guy said it was beyond hope, and he'd have to find another used one to get parts. That's obviously getting harder every year, so I try to take care of the parts I have to keep 'em running smoothly.
Gosh, life was simpler when these toys were just old ratty beaters, and parts were junkyard-plentiful...
- Erik
64 Valiant, 170 3-spd
82 Volvo wagon, 5.0 5-spd :)