NHTSA Complaint #10446922 — 2003 CHEVROLET AVALANCHE 1500

DURING TRIP FROM NC->TX->FL->TX I WAS STOPPED FOR SPEEDING (75 IN 60 ON I-10 IN LA) -- I DO *NOT* KNOWINGLY SPEED. I BEGAN WATCHING MY SPEED TO TRY TO UNDERSTAND WHY THIS HAPPENED. THE PROBLEM REPEATED SEVERAL TIMES ON THIS TRIP, AND I WAS ABLE TO RECORD A NUMBER OF PHOTOS OF THE PRECISE PROBLEM. AFTER DRIVING FOR MORE THAN A COUPLE OF HOURS (PROBABLY WHY I NEVER NOTICED THIS BEFORE), THE SPEEDOMETER WILL BEGIN A VERY SLOW DRIFT DOWNWARD. SINCE I HAD BEEN ON 70MPH ROADS FOR QUITE SOME TIME, I APPARENTLY ADJUSTED MY SPEED CONTROL UP TO MAINTAIN WHAT I THOUGHT WAS 70. THEN, WHEN I REACHED IBERVILLE PARISH IN LA, I NOTICED THE SPEED LIMIT WAS NOW 60; BUT WHEN I LOOKED DOWN, THE SPEEDOMETER WAS CLOSE ENOUGH TO 60 THAT I DIDN'T REALIZE ANYTHING WAS WRONG UNTIL A TROOPER FLAGGED ME DOWN. IN NO POSITION TO ARGUE, I WAS PUZZLED -- UNTIL I REACHED TX WHEN I NOTICED THE SPEEDOMETER DROPPING EVER SO SLOWLY. I HAD NO REAL IDEA OF MY SPEED, SO I JUST STAYED WITH TRAFFIC. A FEW DAYS LATER, ON THE TX->FL LEG, THE PROBLEM RESUMED AFTER A FEW HOURS. THIS TIME, I GOT THE IDEA TO START THE GPS ON MY BLACKBERRY PHONE. SURPRISE! MY REAL SPEED WAS DEFINITELY FASTER THAN INDICATED. SO I BEGAN TAKING PICTURES OF THE SPEEDOMETER AND PHONE. I HAVE A SERIES OF PHOTOS PROVING THE FAILURE. WHAT IS ALSO INTERESTING IS THAT STOPPING AND TURNING OFF THE ENGINE FOR A MOMENT, THE SPEEDOMETER STARTED WORKING AGAIN FOR A WHILE. ############### OVER A YEAR AGO, I HAD A ONE-TIME ISSUE WITH THE SPEEDOMETER. IT INDICATED MUCH FASTER THAN I WAS GOING -- MAYBE 50 WHILE STOPPED. WHEN RESTARTING THE ENGINE, I NOTICED THE NEEDLE "STEPPING" BACKWARDS FOR LESS THAN A SECOND. OUT OF CURIOSITY, I STOPPED AND STARTED THE ENGINE ABOUT 8 TIMES -- EACH TIME THE NEEDLE STEPPED BACKWARDS A FEW MPH, UNTIL IT EVENTUALLY FULLY RETRACTED BACK TO 0 AND WORKED FINE UNTIL THIS LONG TRIP. *TR