2017 GMC SIERRA 3500

My truck is affected by GM’s engine block‑heater safety recall (NHTSA 21V‑496 / GM N212329840) addressing a risk of short circuit and potential engine‑compartment fire at the heater cord/terminal connection. GM’s interim action has been to remove/disable the block‑heater cord, which my dealer did, and then marked the recall “completed.” As a result, the NHTSA VIN tool shows 0 unrepaired recalls, even though no actual repair/restored functionality exists and GM continues to advise owners not to use the block heater until parts are available. Safety concern / impact: I live in a cold‑weather area and purchased this diesel expecting a functioning block heater for reliable cold starts. Disabling the heater has removed an intended cold‑weather safety/starting aid for multiple winters without a final fix. GM’s bulletin explicitly allowed dealers to disable the cord to close the recall, rather than provide a repair, leaving owners without the feature indefinitely. Suspiciously, I have also had to replace glow plugs on this truck sooner than traditional wear / failure rates would demand - including one glow plug that has been replaced twice in short span of time (should have lasted years). I continue to monitor GM’s recall portal; still no parts/remedy schedule. Please review whether GM’s chosen remedy—disabling a safety‑related feature and closing the recall—is adequate and within a reasonable time under the Safety Act. If not, I request NHTSA open a Recall Query into remedy adequacy and timeliness so owners receive a real repair (replacement heater/cord/connector) or appropriate alternative remedies.

My truck is affected by GM’s engine block‑heater safety recall (NHTSA 21V‑496 / GM N212329840) addressing a risk of short circuit and potential engine‑compartment fire at the heater cord/terminal connection. GM’s interim action has been to remove/disable the block‑heater cord, which my dealer did, and then marked the recall “completed.” As a result, the NHTSA VIN tool shows 0 unrepaired recalls, even though no actual repair/restored functionality exists and GM continues to advise owners not to use the block heater until parts are available. Safety concern / impact: I live in a cold‑weather area and purchased this diesel expecting a functioning block heater for reliable cold starts. Disabling the heater has removed an intended cold‑weather safety/starting aid for multiple winters without a final fix. GM’s bulletin explicitly allowed dealers to disable the cord to close the recall, rather than provide a repair, leaving owners without the feature indefinitely. Suspiciously, I have also had to replace glow plugs on this truck sooner than traditional wear / failure rates would demand - including one glow plug that has been replaced twice in short span of time (should have lasted years). I continue to monitor GM’s recall portal; still no parts/remedy schedule. Please review whether GM’s chosen remedy—disabling a safety‑related feature and closing the recall—is adequate and within a reasonable time under the Safety Act. If not, I request NHTSA open a Recall Query into remedy adequacy and timeliness so owners receive a real repair (replacement heater/cord/connector) or appropriate alternative remedies.

The contact owns a 2017 GMC Sierra 3500. The contact stated that while shifting from park(P) to drive(D), the engine revved, but the vehicle failed to move forward. There were no warning lights illuminated. The vehicle was towed to a certified mechanic, who determined that the vehicle needed to be diagnosed by a dealer. The mechanic was able to shift the transmission into manual drive mode, allowing the contact to drive the vehicle to the residence. The dealer was contacted and informed the contact that the VIN was not under recall. The vehicle was not repaired. The manufacturer was informed of the failure and referred the contact back to the dealer for assistance. The failure mileage was approximately 120,000.

The contact owns a 2017 GMC Sierra 3500. The contact stated while driving 30 MPH, there was smoke and a squealing sound coming from the passenger’s side rear wheel. The vehicle was taken to the residence and the contact observed fluid on the axle tube. The contact stated that the axle as taken apart and the wheel bearings were in pieces. The contact stated that the axle nut had unintendedly backed off. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 25,000.

Trailer brake system connection warning Intermittent when towing it will say trailer not connected, while still having a secure 7 pin connection. This causes me to loose trailer brakes. My camper is nearly 14,000 lbs. Very dangerous situation. Happened since new. Was into / complained to GM service dept over 6 times.

Trailer brake system connection warning Intermittent when towing it will say trailer not connected, while still having a secure 7 pin connection. This causes me to loose trailer brakes. My camper is nearly 14,000 lbs. Very dangerous situation. Happened since new. Was into / complained to GM service dept over 6 times.

this vehicle is garage kept and meticulous maintained, has 136,000 miles, original owner, brought to dealer for an oil leak, they said exhaust are frozen and won't come out after heating etc. they have to replace exhaust manifolds! Bolts should not seize is the head of a garage kept vehicle that's heated! Being a mechanic many years ago I have never seen this happen! this is the first year for the new engine, On a internet search I found it's not uncommon, and the bill is going to cost me over $8000 !. Thank you, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

tHE 6L90 TRANMISSION FAILED WITH NO WARNING AT 58,408 MILES. HAD TO BACK THE TRUCK UP IN TRAFFIC OVER 1/2 MILE TO REACH A SAFE SPOT. SEEMS GM IS HAVING A LOT OF PROBLEMS WITH THIS TRANSMISSION AND THEIR 8 SPEED TRANSMISSION. NO ASSISTANCE FROM GM TO REPAIR SEEING I WAS OUT OF THE 5 YEAR 100000 WARRANTY. SEEMS GM KNOW ABOUT THESES PROBLEMS. HAD TO SPEND $5K TO GET NO DEALER SERVICE TO INSTALL A REMANUFACTURED TRANS, HOPING IT WILL NOT HAPPEN AGAIN

SERVICE TRAILER BRAKING SYSTEM. Faulty control in the dash. Known issue per mechanic but no recall issued. Safety issue as trailer brake may not function properly when towing as a result

SERVICE TRAILER BRAKING SYSTEM. Faulty control in the dash. Known issue per mechanic but no recall issued. Safety issue as trailer brake may not function properly when towing as a result

Brake are very spongy all the time we’ll While driving in parking lot at low speed we lost brakes happen to hit person in front. This has been a continuous problem to point we are scared to even use the truck to go to store. Took it to Firestone. They told me it was the master cylinder. So they replaced that, replaced the front rotors and pads, did a fluid exchange abs as well? Don’t know what that is. On the internet there is tons of this issue. I even see GMC 1500 is having this issue and there is a recall for the recalibration electric brake controller? Couldn’t it include the full Sierra line?. Why not on the 2500, 3500? Looks to be same system? Rotors and calipers are different thats it If anyone can help please let me know. It’s not covered under warranty and they want to replace some pump for $1500. I just paid $1500 for something totally different

The contact owns a 2017 GMC Sierra 3500. The contact received notification of NHTSA Campaign Number: 21V496000 (Equipment) however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.

WHEN YOU PUT ON THE BRAKES YOU HAVE TO PRESS SO HARD AND I MEAN HARD TO GET IT TO STOP. IT WAS NOT LIKE THAT WHEN IT WAS NEW. IT YOU PUT ATRAILER BEHIND THE TRUCK AND THE TRAILER HAS BREAKES THAT IS WHAT STOP THE TRUCK NOT THE TRUCK BRAKES. IT IS SAFE TO DRIVE. IT HAS BEEN GOING ON FOR ABOUT 3 MONTH.19/2019

WHILE DRIVING DOWN A MOUNTAIN ROAD WITH A 5TH WHEEL ATTACHED IT APPEARED THAT THE REAR BRAKES ON THE DRIVERS SIDE WERE SMOKING, I PULLED OVER TO ALLOW IT TO COOL. WE FOUND A GMC DEALERSHIP AND PROCEEDED THERE VERY SLOWLY STOPPING A NUMBER OF TIMES TO ALLOW THE BRAKES TO COOL DOWN. 2 MILES SHORT OF GMC, THERE WAS A LOUD POP AND A TIRE HAD BLOWN. WE PULLED OVER AND WHILE CALLING ROADSIDE ASSISTANCE NOTICED FIRE UNDER THE TRUCK. WE PUT IT OUT WITH A FIRE EXTINGUISHER BEFORE THE FIRE DEPARTMENT ARRIVED. WE WERE TOWED TO THE DEALERSHIP. THE BRAKE CALIPER CAME APART, THE REAR AXLE BROKE (POSSIBLY MELTED FROM HEAT AND FIRE?). GM INITIALLY STATED 4 DAYS TO REPAIR, NOW THEY THEY ARE SAYING 3 WEEKS AS THEY HAVE TO BUILD A NEW AXLE. IF WE HAD NOT HAD THE EXTINGUISHER THE TRUCK, RV AND MEADOW WOULD HAVE ALL GONE UP IN FLAMES AND WHO KNOWS THE DISASTER THAT COULD HAVE OCCURRED IF THIS HAPPENED ON THE MOUNTAIN ROAD. THIS VEHICLE ONLY HAS 17,000 MILES, 11 MONTHS OLD AND HAS HAD ALL ROUTINE MAINTENANCE PERFORMED AT GMC DEALERS. I HAVE MORE PICTURES BUT AM UNABLE TO UPLOAD THEM.

WHILE DRIVING DOWN A MOUNTAIN ROAD WITH A 5TH WHEEL ATTACHED IT APPEARED THAT THE REAR BRAKES ON THE DRIVERS SIDE WERE SMOKING, I PULLED OVER TO ALLOW IT TO COOL. WE FOUND A GMC DEALERSHIP AND PROCEEDED THERE VERY SLOWLY STOPPING A NUMBER OF TIMES TO ALLOW THE BRAKES TO COOL DOWN. 2 MILES SHORT OF GMC, THERE WAS A LOUD POP AND A TIRE HAD BLOWN. WE PULLED OVER AND WHILE CALLING ROADSIDE ASSISTANCE NOTICED FIRE UNDER THE TRUCK. WE PUT IT OUT WITH A FIRE EXTINGUISHER BEFORE THE FIRE DEPARTMENT ARRIVED. WE WERE TOWED TO THE DEALERSHIP. THE BRAKE CALIPER CAME APART, THE REAR AXLE BROKE (POSSIBLY MELTED FROM HEAT AND FIRE?). GM INITIALLY STATED 4 DAYS TO REPAIR, NOW THEY THEY ARE SAYING 3 WEEKS AS THEY HAVE TO BUILD A NEW AXLE. IF WE HAD NOT HAD THE EXTINGUISHER THE TRUCK, RV AND MEADOW WOULD HAVE ALL GONE UP IN FLAMES AND WHO KNOWS THE DISASTER THAT COULD HAVE OCCURRED IF THIS HAPPENED ON THE MOUNTAIN ROAD. THIS VEHICLE ONLY HAS 17,000 MILES, 11 MONTHS OLD AND HAS HAD ALL ROUTINE MAINTENANCE PERFORMED AT GMC DEALERS. I HAVE MORE PICTURES BUT AM UNABLE TO UPLOAD THEM.

WHILE DRIVING DOWN A MOUNTAIN ROAD WITH A 5TH WHEEL ATTACHED IT APPEARED THAT THE REAR BRAKES ON THE DRIVERS SIDE WERE SMOKING, I PULLED OVER TO ALLOW IT TO COOL. WE FOUND A GMC DEALERSHIP AND PROCEEDED THERE VERY SLOWLY STOPPING A NUMBER OF TIMES TO ALLOW THE BRAKES TO COOL DOWN. 2 MILES SHORT OF GMC, THERE WAS A LOUD POP AND A TIRE HAD BLOWN. WE PULLED OVER AND WHILE CALLING ROADSIDE ASSISTANCE NOTICED FIRE UNDER THE TRUCK. WE PUT IT OUT WITH A FIRE EXTINGUISHER BEFORE THE FIRE DEPARTMENT ARRIVED. WE WERE TOWED TO THE DEALERSHIP. THE BRAKE CALIPER CAME APART, THE REAR AXLE BROKE (POSSIBLY MELTED FROM HEAT AND FIRE?). GM INITIALLY STATED 4 DAYS TO REPAIR, NOW THEY THEY ARE SAYING 3 WEEKS AS THEY HAVE TO BUILD A NEW AXLE. IF WE HAD NOT HAD THE EXTINGUISHER THE TRUCK, RV AND MEADOW WOULD HAVE ALL GONE UP IN FLAMES AND WHO KNOWS THE DISASTER THAT COULD HAVE OCCURRED IF THIS HAPPENED ON THE MOUNTAIN ROAD. THIS VEHICLE ONLY HAS 17,000 MILES, 11 MONTHS OLD AND HAS HAD ALL ROUTINE MAINTENANCE PERFORMED AT GMC DEALERS. I HAVE MORE PICTURES BUT AM UNABLE TO UPLOAD THEM.

HEADLIGHTS SHAKE OR FLICKER AT THE SLIGHTEST BUMP OR CRACK IN ROAD. GM IS AWARE OF THE PROBLEM BUT HAS NO FIX NOR DO THEY PLAN TO.

PURCHASED A NEW 2017 GMC DENALI 3500. THE TRUCK CAME WITH 4 MICHILEN LT 265/70R18 A/T2 TIRES ON IT. THE SPARE TIRE IS A GOODYEAR TIRE. PAGE 401 AND PAGE 402 OF THE OWNERS MANUAL STATES: MIXING TIRES OF DIFFERENT SIZES,BRANDS, OR TYPES MAY CAUSE LOSS OF CONTROL OF THE VEHICLE, RESULTING IN A CRASH OR OTHER VEHICLE DAMAGE. USE THE CORRECT SIZE, BRAND, AND TYPE OF TIRES ON ALL WHEELS."