My speedometer suddenly JUMPED to 80mph

2003 CHEVROLET TRUCK
90,000 MILES • V8 • 2WD • AUTOMATIC
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WORM3197
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  • 1 POST
My speedometer suddenly JUMPED to 80mph, as I was only doing around 30mph. When I stopped and cut the engine, it dropped to 60mph and stayed. When I would start again it would start at 60 as if that was 0. I heard it could be as simple as a speedometer cable, but was also told it could severely affect my transmission.
Dec 13, 2009 at 7:32 AM
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DR LOOT
  • ✓ASE Certified Mechanic
  • 2,311 POSTS
  • ASE Certified Mechanic
first of all, there is no speedometer cable on that truck, it is computer-controlled, called VSS vehicle speed sensor, it is located on the left side of the transmission check out the diagrams below to show you the location. Check out the diagrams (Below). Let us know what happens and please upload pictures or videos of the problem.

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Apr 21, 2021 at 12:29 PM
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