Broken speedometer

[alolmo]

My speedometer is not working, and before I take it out and replace it or whatever, I would like to know if it is possible to fix it. Have any body done this? My speedometer’s needle seems to be stuck but it still counts miles. ’70 gt.

[BQS4]

It'd be easier, in the long run, just to go ahead and replace it. Just make sure the "W=XXXX" rating is the same.

[GTJIM]

Yes - We can! BUT you need to find a VDO agent that still does fix-its.

Not so simple these days - so easier to just find a replacement used one.

On the front of the gauge, just under the spindle for the needle there is a number written like "W=1062' or something similar. That is the W=XXXX rating that Gene has mentioned - it is actually the number of revolutions the speedo cable does per mile. That is why you need to replace yours with one that has the same number - there are 3 or 4 different ones.

Other than that all GT speedos look the same.

[hrcollinsjr]

That is why you need to replace yours with one that has the same number - there are 3 or 4 different ones.

Different speedometers Jim is talking about.


As far as matching the one you have, Jim is assuming you have the correct one to start with. It is so easy to mix and match parts from different years on these cars you should really check to see which trans you have. The trans with an external reverse light switch actuated on the driver's side by the shift linkage uses the W=897 speedo and if it is an A/T trans OR a M/T trans with the reverse light switch screwed in to the top right rear of the trans then you will need the W=1062. If you plan to swap to a 5 speed Getrag at a later date you will need the W=1062.

HTH,
Harold

[jlthunder]

The speedo is pretty simple inside. I opened a "broken" one with a stuck needle. It is hard to explain, but the there is a set screw which was holding the needle. I loosened it a 1/16th of a turn, and the unit was working again. I never installed it in a car, but it read 70 mph when I hooked it up to my drill. I got the same reading on a different speedo.

Take it apart by first removing the glass bezel and go from there. It is already broken, so what damage could you do?

[alolmo]

Thanks guys, very helpful information. I hadn’t notice the “w” rating you all were talking about. My speedo, being not original to my car is the correct one for it, as per your info w=897. I think I’ll eventually open it up when I get it out (not looking forward to do that) but not before I have another one in-waiting.
Thank you all for the help.
Al

[euphorium]

Have you taken into account the possiblity that your pinion gear could be broken? IMy speedometer is not working because of this reason. Just a thought.

Good luck..

[alolmo]

Yes I had, my speedo indicator is stucked at "90" I don't know how it got there

[markandson]

This speedo problem is exactly what I experienced when I first got my GT on the road. The tiny needle bearing, like a watch balance wheel, gets rusty or the grease gets old and sticky. I opened mine up and cleaned it. I did this to two different units, one worked and one did not. When re-assembling you have to be careful not to bind the little bearing.