1976 Corvette Speedometer malfunction
Thread Starter
3rd Gear
Joined: Mar 2014
Posts: 3
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From: Mechanicsburg Pennsylvania
1976 Corvette Speedometer malfunction
Why does my speedometer needle fluctuate wildly and is ~20 MPH slower than GPS? What can I do to fix it? Thanks.
Last edited by ccurry7044; Sep 14, 2019 at 11:27 AM.
Race Director
Joined: May 2006
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Do you have cruise control?
Has the speedometer always been off by 20 mph or this started with the needle fluctuation?
Have you checked the condition of the cable or cables going to the speedometer?
They can be lubricated but the proper lubricant must be used and only used on areas not near the speedometer head.
Has the speedometer always been off by 20 mph or this started with the needle fluctuation?
Have you checked the condition of the cable or cables going to the speedometer?
They can be lubricated but the proper lubricant must be used and only used on areas not near the speedometer head.
Thread Starter
3rd Gear
Joined: Mar 2014
Posts: 3
Likes: 0
From: Mechanicsburg Pennsylvania
Thanks for your quick reply. In response to your questions, I do have cruise control but have never used it so I am not sure it even works. I installed a new cable about a year ago yet the fluctuating needle continues to randomly occur when the engine is cold but settles down after several miles of driving. I will try your suggestion to lubricate the cable. The mph variation only started recently after I had a new clutch and pressure plate installed but I can't imagine how that would have affected the speedometer. A local mechanic suggested that I may need to replace the entire speedometer assembly but unfortunately I am unable to find one for the '76 although they are available for 68-75 or 77 and newer.
