2003 GMC Sierra 1500

WHILE GOING DOWN THE ROAD MY SPEEDOMETER WAS SHOWING 120MPH AND I WAS ONLY RUNNING 75MPH. WHEN I STOP AND SHUT OFF MY VEHICAL THE SPEEDOMETER READS 45MPH INSTEAD OF 0MPH. IF YOU SWITCH THE IGNISTION OFF AND ON SEVERAL TIMES IT WILL EVENTUALLY GO BACK TO 0MPH. I WAS DOING SOME RESEARCH ON IT AND FOUND THIS WEB SITE WWW.TOPIX.NET. I FOUND OUT PRETTY QUICK THIS IS NOTHING NEW. THERE WERE SO MANY LISTINGS ON THERE FOR THE SAME PROBLEM THAT IT WAS UNREALISTIC. I HAVE ALWAYS OWNED CHRYSLER PRODUCTS UNITLL I PURCHASED MY GMC. I HAVE DONE NOTHING BUT BRAGG ABOUT HOWW I DON'T NEVER HAVE PROBLEMS WITH THIS TRUCK BUT NOW SEEING ALL OF THESE COMPLAINTS FOR THE SAME THING I KINDA FEEL LIKE AN IDIOT. THIS IS A VERY BIG SAFETY ISSUE EXSPECIALLY WHEN TRAVELING THE INTERSTATES. THIS COULD CAUSE SOME PRETY SERIOUS WRECKS WHEN YOUR SHOWING YOUR RUNNING 100MPH AND ONLY DOING 60MPH. THATS ASKING FOR A MAJOR REAR END COLLISION. IF ANY ONE IS LISTENING AND IS CONSERNED ABOUT THE CONSUMERS SAFETY THEN SOMETHING NEEDS TO BE DONE PRETTY QUICK. I HAVE READ WHERE CONSUMERS HAVE SPENT THOUSANDS OF DOLLARS TO MAKE THIS REPAIR. WITH AS MANY COMPLAINTS I HAVE READ THERE SHOULD BE SOMETHING DONE PRETTY QUICK BEFORE SOMEONE GETS INJURED OR EVEN KILLED. SO IF ANY ONE CARES DO SOMETHING ABOUT IT. *NM