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Crazy speedometer?

1914 Views 13 Replies 10 Participants Last post by  Pops @
Sometimes as i'm driving i'll hear a buzzing or a whirring sound coming from the dash, and when this happens the speedo goes way up to 90-100mph when i'm only going about 60. Any clues?
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speedometer cable needs removed, cleaned and so before it breaks. I use ATF.:wavey:
Ok, so how exactly do I go about it?
The best way is to remove it from the car. Under the dash(PITA) unscrew the fitting from the gauge may have to remove the cluster(also a PITA)to get it loose, then at the transmission unscrew the fitting...remove the cable. Then as has been said use ATF to "pour" into the fittings and cable(messy)to clean/lubricate it, twisting the square projection at the end of the cable while doing so.

Or you could purchase a new cable from one of the suppliers:)

But you should address this asap otherwise you may experience speedometer failure(EXPENSIVE TO REPLACE and a whole new can of worms is opened, been there,done that)

when this happened to my wife is her car. it turned out to be the speedo head the shaft to disk solder broke. she bought a used unit.. :wavey:
Bobby got it right on- I had identical problem. Took my sweet time getting to it and cable snapped. opps.
Ok, I pulled the cable through the dash and getting to it was alot easier than I had expected. I used white lithium grease, I applied it the first time and the needle stabilized and was working normally again. I pulled over and put some more on, and it improved even more. Thanks you guys, I would've ended up snapping it if it weren't for your help! :shakehands:
It's going up to 90 because it is being wound up like a spring due to no lubrication. Try to find some graphite grease. Disconnect the cable from the speedometer by unscrewing the outer ring then pull the cable out. Wear gloves and lubricate the cable with the graphite grease and side it back in until it seats in the tranny then install in the speedo and tighen up the outer ring. Jim
I read somewhere that you specifically shouldn't use graphite, and that lithium grease was the way to go.
You shouldn't use graphite alone. It's a mixture of it and grease. I've seen it in most 55-57 speedometers.
I had something similar happen in my 57 but I replaced my speedo cable and the noise was still there. Then the needle stared to bounce around after it got past 30 mile an hour. I bought a reconditioned speedo head and problem solved. Now we dont talk as loud and I know exactly what speed I am doing instead of all the guess work.
Crazy Speedo

Hi, I had a similar problem, but it was the speedo itself that went crazy. The first sign was a 90 MPH then 120 & 200 that broke & popout the needle. It may need some lube or to be change for a rebuilt. I bought a rebuilt on eBay since inner parts were in bad shape with over 200,000 miles. :anim_25:
GJ....If lubing the cable does not fix it, you'll have to try lubing the speedo head itself.....See link: However, be super careful, when removing the 55/56 needle, as they are not reproduced that I know of.
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