Speedometer crapping out??

[69wannabe]

Got in my charger to go for a saturday afternoon spin and the speedometer was bouncing around a good bit. it usually bounces a little bit but is usually fairly steady at higher speeds (50 to 100) but today at 70 mph it's bouncing everywhere and making a grinding or a rough noise at the speedometer.

My first thought was the cable so I reached up behind the cluster and dropped the cable down and pulled it out to see if it was binding but it slid out smoothly and didn't seem to be a catch or problem with the cable. I sprayed lube down the cable housing and greased the cable good and put it back in there hooked it back up and it didn't change anything so I am wondering if my speedometer has a problem inside it.

Anybody else have this problem? I have had all the other gauges and the tach and clock all rebuilt by redline gaugeworks but nothing done to the speedometer. May be time for a speedo rebuild or replacement.......

[XH29N0G]

My understanding is that bounding in the speedometer needle can originate with the cable binding or with something binding in the speedometer head itself (where the magnet spins and causes the needle to deflect).  This can be dust or oil in the mechanism.  I do not know how to clean them properly and wrestled with this myself until I finally gave up and bought a replacement.  I know there are shops like redline that fix them.

[69wannabe]

My understanding is that bounding in the speedometer needle can originate with the cable binding or with something binding in the speedometer head itself (where the magnet spins and causes the needle to deflect).  This can be dust or oil in the mechanism.  I do not know how to clean them properly and wrestled with this myself until I finally gave up and bought a replacement.  I know there are shops like redline that fix them.

I don't think the cable is the problem but I may be wrong, when I pulled the cable out of the housing it just slid out easily and didn't bind at all. Going back was the same and I spun it and it was pretty smooth in the housing. I have another speedometer but i'm not sure if it's any good or not. Maybe redline will give me a good deal on fixing it since a new one is 300+ from the resto places....

[birdsandbees]

Save yourself the possible heart ache! Make a small square joiner from a piece of square stock, put it in a cordless drill .. then into the speedo input and run it counterclockwise to see if your speedometer runs smooth. I bet it does... Then it's your cable binding / twisting or a trans gear issue.

[XH29N0G]

Save yourself the possible heart ache! Make a small square joiner from a piece of square stock, put it in a cordless drill .. then into the speedo input and run it counterclockwise to see if your speedometer runs smooth. I bet it does... Then it's your cable binding / twisting or a trans gear issue.

I was just about to suggest this test and agree fully.  Make sure the drill is spinning the correct way (I don't recall riche now whether it is reverse or forward).  For the square piece, I believe I used a wooden match stick.

If you know how fast the drill spins it is also possible to check the speedo calibration. 

[69wannabe]

I will try that and see, it's weird that the speedo is making an awful noise tho. I have a few more things to do on my buddy's charger and then I will pull the cluster and see whats up with the speedometer. I may get me a new cable just because my cable has a place on it where it got on the header and burnt a place on it but it has been that way for a long time and hasn't really been an issue but it does have a burnt place on it.

[Alaskan_TA]

Another thing that can cause this is that the speedometer end is not fully engaging the gauge drive.

Try this & then take it for a test drive;

Loosen the cable from the transmission.

Hold the outer cable housing jacket while pushing the inner drive cable back up, towards the speedometer.

Giving it a gentle twist may help.

If it moves up, you should feel it, but it will not be much.

Re-install & test drive.

[A383Wing]

the squealing is probably coming from the speedo head bushing inside...I bet it's dry and worn out.....I had the same issue in my car....it was not the cable

[69wannabe]

Another thing that can cause this is that the speedometer end is not fully engaging the gauge drive.

Try this & then take it for a test drive;

Loosen the cable from the transmission.

Hold the outer cable housing jacket while pushing the inner drive cable back up, towards the speedometer.

Giving it a gentle twist may help.

If it moves up, you should feel it, but it will not be much.

Re-install & test drive.

I think if it was the cable it wouldn't have just started this all of a sudden, like the next post said I believe it's the speedo itself. Haven't had time to get out there and see about it but maybe this weekend I will get it apart and see what's up with it.

[72Charger72]

Had the same thing yrs ago replaced cable problem solved.

[69wannabe]

Well I may be wrong about the speedo cable (nothing new) since today the weather was really nice and this time of the year you never know about the weather and by now it's usually crappy so knowing my speedometer was not working properly I decided to go for a drive anyway. Pulled out on the road and the speedometer wasn't bouncing around and wasn't making any noise. Hmmmmm, I thought it was odd but it was warmer today than last sunday which may or may not made any difference and the lube I sprayed down the housing may have made it's way down to the bottom of the housing making a difference too. either way it is working good for now and if it craps out again I am going to replace the cable first and go from there.

Was able to enjoy it for today without a noisy speedometer and a bouncing needle at least......

[XH29N0G]

That is good news.