NHTSA Complaint #10576549 — 2012 CHEVROLET SILVERADO

THIS FAULT HAS BEEN PRESENT SINCE THE FIRST WEEK OF OWNING MY 2012 SILVERADO CREW CAB LT EQUIPPED WITH THE 5.3 LITER AND 6 SPEED TRANSMISSION. UPON SLOWING TO A STOP, THE TRUCK SURGES AND LUNGES FORWARD AS THE TRANSMISSION DOWNSHIFTS BETWEEN GEARS, AND IS MOST NOTICEABLE WHEN TRAVELING UP OR DOWN HILLS. THE FAILURE MODE CAN BE TECHNICALLY DESCRIBED AS THE FOLLOWING SEQUENCE OF EVENTS: 1. SLOWING TO A STOP (COASTING), ENGINE BEGINS RIDING OUT 4TH GEAR (FOR EXAMPLE). 2. APPLY BRAKES; TRANSMISSION DOWNSHIFTS TO 3RD, AND ENGINE RPMS INCREASE TO COMPENSATE FOR DYNAMICS OF SHIFTING. TORQUE CONVERTER IMMEDIATELY ENGAGES THE ENGINE TO THE WHEELS. AS THE ENGINE IS AT A HIGH RPM LEVEL, AN ACCELERATING LOAD IS APPLIED TO THE WHEELS, WHILE BRAKING. 3. THIS CREATES AN UNINTENDED SURGE OF ACCELERATION, WHICH IS THEN ALSO NOTICEABLE THROUGH THE REMAINING GEARS (TRUCK SLOWS, THEN SURGES, SLOWS, THEN SURGES UNTIL COMING TO A COMPLETE STOP). I HAVE ALSO VERIFIED THAT THIS IS A COMMON COMPLAINT IN THE ONLINE FORUMS, AND MANY PEOPLE ARE EXPERIENCING THIS FAULT. IN FACT, ONE OF THE DEALERSHIPS ACTUALLY INFORMED ME THAT MANY OF HIS CUSTOMERS GO TO AN AFTERMARKET SHIFT PROGRAM TO AVOID THE ISSUE. I HAVE TRIED THIS, AND IT DID NOT RESOLVE THE ISSUE. EACH TIME THE TRANSMISSION IS EVALUATED AT THE DEALERSHIP, THE DAPS (DIGITAL PARAMETERS) ARE "RESET" (ACCORDING TO THE SERVICE SHOPS), AND THE TRUCK DRIVES FANTASTICALLY. HOWEVER, ROUGHLY 10 MILES LATER, IT IS BACK TO EXHIBITING THE EXACT SAME FAILURE MODE. DEALERSHIP HAS TROUBLESHOOT THIS FAULT EXTENSIVELY, AND HAS STATED THAT THIS MODE OF OPERATION IS "NORMAL" - I ASKED THEM TO EXPLAIN HOW FORWARD ACCELERATION DURING BRAKING WAS "NORMAL", AND OF COURSE THEY COULD NOT. *TR