Speedometer gone WACKO...

[elGordo0524]

After being on the highway at 70mph for approx 1.5 hours....got off at off ramp and the speedo only decreased to about 50mph and I was at the off ramp stop sign. Anyone know what this means for me? Also just in the past week or two have been experiencing some hard shifts from 1st to 2nd gear in the am only. Could these things be related?

2004 Silverado 1500 w. approx 110,000 miles. v8, Auto Trans.

Gordo

[DIGS16]

ur speedometer is broken... same thing happen to me a few years ago coming back from santa barbara speedo said iwas going 120 lol hahaha go to the dealership and they will repair it... it happen to so many trucks and suv that they did a recall or something

[Crawdaddy]

I disagree with Digs. Since you are having both speedo AND tranny shifting issues, I'm guessing that you have an issue with the speed sensor circuit, either a bad sensor or messed up wiring. Do you have a check engine light? If so, pull the codes or have them pulled for you at a local auto parts store. If it's the speed sensor circuit, you almost certainly have a CEL to go with it. That would explain both issues. If it were just the whacked-out speedo, I would agree with the bad instrument cluster. Good luck!

[elGordo0524]

No check engine light yet. when the speedo first acted up, i checked all the fuses and even disconnected the battery and that reset the speedo to its regular function. Trouble is, this is only a temporary fix tot he speedo and the hard shifting from 1st to 2nd is still present at low speed (moving in rush hour LA traffic). If I leave a stop sign and accelerate like I want to go somewhere, the shift from 1st to 2nd is smooth as butter.

Would love to know what the Speed sensor is. Where is it located? Something a novice repair person like me could handle?

THANKS FOR THE ANSWERS CRAWDADDY!!!

Much appreciated!!

GJ

[dsfloyd]

The instrument cluster is something that goes bad on that year model. Mine is getting replaced now because of the same speedo issue but the oil pressure gauge would wig out too. they replace it free up to 70k so unfortunately for you it is no longer free.