Speedomter options ?

[JTW_Jr]

Tonight the speedo started making a horrendous noise , MPH gauge is not moving at all , the odometer is just kind of twitching....

Options in the event it isn't repairable.

This is in a 72 F100 with a 390 and a C6. Rear end has 3:55's ( Auburn locker ).

Will either of these work as replacements without too much work ?

http://stores.newvintageusa-store.com/- ... Detail.bok

http://autoplicity.com/products/268010- ... meter.aspx

[HIO Silver]

There are four things that could be malfunctioning:

1. The drive gear in the tranny;
2. The driven gear at the end of the speedo cable;
3. The speedo cable itself; or,
4 The guts of the speedo assembly.

From most common to least common, it's 3, 2, 4, and 1. However, check that the speedo cable hasn't loosened from the back of the instrument cluster..... it's a square drive and could just be loose and intermittently catching the speedo.

Moving on to real troubleshooting... pull the speedo cable out of the trans and attach to a drill driver. Spin it while having a helper observe the speedometer. Still don't work? Remove the speedo cable from the truck. Do the same thing while observing the output end.... it should spin at the same rate. No? Then the unit in the instrument cluster may be bad.

[JTW_Jr]

Thanks. I will begin checking in the am, was too dark out to keep diagnosing, I did check that the cable is tight at the back of the speedometer. Will check the other stuff tomorrow first thing.

Be nice if it is fixable.

[70shortwide]

what ive done in the past is just pull the cable loose from the cluster (you should be able to weasel your hand back there without pulling the cluster). pull it down to where you can see it and drive around the block.. should be apparent if its operating smoothly or not. if the cable operates smoothly, your issue would be in the cluster.

[JTW_Jr]

Hooked up the cordless Makita to the cable at the transmission end...noise is still there. Pulled the gauge panel , this speedo is toast.

Looks like a bunch of angry beavers have been chewy on this thing for a long time. Which explains why the odometer hadn't worked in awhile.

Checked all the junkyards around this side of town, not a single bumpside in the yards. Hoping to hit the North side of town junkyards tomorrow.

[flyboy2610]

You might try posting something in the parts wanted section of the main forums page. Seem like someone is always parting out a truck.

[Randle]

JTW_Jr have you found a good speedometer, I was looking though my parts and have a couple extra.

[JTW_Jr]

I will be getting one from a guy on the FB ford page, as soon as I recoup from some unexpected expenses ( new washing machine ).

In the mean time I cleaned up the dash by giving it a fresh coat of Wimbledon white via rattle can. Wasn't worried about a show look, just a bit cleaner.

[Randle]

OK Just wanted to make sure you had what you needed

[JTW_Jr]

Some unexpected bills had me waiting to get the speedo, wife surprised me when she found a wrecking yard that had the whole entire gauge cluster for $30! Got the old bumpside back on the road today !

[flyboy2610]

[Randle]

Proud your back on the road.