2020 GMC Sierra 1500 Engine

Diesel exhaust fluid heater short circuits due to poor design. This issue occurs multiple times, including after being repaired. The failure limits the trucks capabilities until it is entirely unusable.

A VERY STRONG "AMMONIA" ODOR COMES INTO THE CABIN. THIS HAPPENS WHEN THE DEF FLUID IS GOING INTO THE EXHAUST SYSTEM FOR THE REGEN PROCESS. THE ODOR MAKES PEOPLE INSIDE NAUSEOUS AND DIZZY. MUST OPEN WIDOWS OR STOP AND GET OUT OF THE VEHICLE. OUR GMC DEALER CAN FIND NO CODES OR PROBLEMS WITH THE EXHAUST SYSTEM. WE HAVE ALSO NOTICED THAT THE DEF FLUID HAS GONE DOWN VERY QUICKLY SOMETIMES DURING THIS EVENT. IT IS RANDOM. SOME DAYS NOTHING, OTHER TRIPS 3 AND FOUR TIMES THAT THE ODOR OCCURS. LOOKING ONLINE- THERE HAVE BEEN MANY POST ABOUT THIS PROBLEM.

Repeated issues with exhaust and emissions components.

Rear main oil seal failure causing truck to lose all oil, leaking all over truck, trail leading to drive and garage; possibility of engine seizing up while driving causing an accident, confirmed by dealer, covered by warrenty, is a known issue, no warning lights, messages, or other symptoms of problem, NHSTA has issued a bulletin for this problem

Found improperly installed rear seals. The truck leaked oil and had to be towed to gmc dealership in Monahans Texas to be repaired. 1 month later the truck leaked oil again.

The contact owns a 2020 GMC Sierra 1500. The contact stated that shortly after refueling while driving under 15 MPH, the check engine and service emissions warning light illuminated. The contact stated that an unknown reset was performed related to TSB: 10173675 (Engine). The vehicle was not yet fully repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 46,000.

AT ABOUT 3500 MILES LIFTERS ON TWO CYLINDERS COLASPED. TOOK TO DEALER THAT DEALER HAD THREE WEEKS BUT FIXED IT. 1500 MILES LATER AT 5036 MILES IT HAPPENED AGAIN ON A DIFFERENT CYLINDER. NUMBER 8. THE FIRST TIME IT WAS 3 AND 5. THE FIRST TIME THE DEALER REPLACED ALL 8 CYLINDERS. SO CYLINDER NUMBER 8 WAS NEW AS WELL. GMC HAS SAID THERE IS NOTHING ELSE THAT CAN BE DONE TO FIX THE ISSUE. THE SECOND DEALER SERVICE MANAGER STATES THAT HE WOULD NOT TRUST IT EITHER TO GO ANY LONG DISTANCE . ALSO STATED THAT THEY HAVE PUT 3 SETS IN TO ONE VEHICLE BEFORE. AS AN ASE MASTER CERTIFIED TECHNICIAN I FIND THIS DISTURBING. I ALSO WAS A GMC,PONTIAC, OLDSMOBILE MASTER TECHNICIAN. THIS IS UNEXCEPTABLE FOR GM TO THINK THIS IS OK TO TAKE PEOPLE'S HARD EARN MONEY AND NOT FIX THERE ISSUES OR MAKE IT RIGHT. I OWNED A 2014,2016,2018 SILVERADO'S THAT HAD NO ISSUES WHAT SO EVER. TO MAKE THINGS WORST GMC ROAD SIDE ASSISTANCE FORGOT ABOUT THE TRUCK BROKE DOWN IN 7 DEGREE WEATHER WITH 35 MILE AN HOUR WINDS. FOR OVER 24 HOURS AND SEVERAL CALLS BACK TO FINALLY GET A SUPERVISOR TO SPEAK TO. TWO DEALERS SAY THAT IT IS UNACCEPTABLE EXCEPT THE CURRENT DEALER THAT IS DEALING DIRECTLY WITH GMC. ANYONE CAN DO A SEARCH ON GM TRUCK LIFTERS COLLAPSING AND YOU IMMEDIATELY OVERWHELMED WITH INFO. IT IS ALSO DISTURBING THAT A DEALERSHIP SERVICE MANAGER SAYS WE COULD PUT A NEW ENGINE IN AND THE SAME THING COULD HAPPEN. THAT TO ME IS POOR QUALITY CONTROL AND POOR CUSTOMER SERVICE. I HAVE ALWAYS BEEN A GM ENTHUSIASTS BUT THIS WILL BE MY LAST ONE. HORRIBLE CUSTOMER SERVICE AND DO NOT BUILD A GOOD PRODUCT OR STAND BEHIND IT. GM SHOULD BE ASHAMED OF THERE FALL FROM GRACE. THIS ALL HAPPENED JUST DRIVING ONCE TO WORK AND ONCE HAULING A ATV ON A TRAILER.

TL* THE CONTACT OWNS A 2020 GMC SIERRA 1500. THE CONTACT STATED THAT THE VEHICLE PUSH START BUTTON AND KEY FOB FAILED TO START THE VEHICLE ON FIRST ATTEMPT. THE CONTACT STATED THAT THE VEHICLE STARTED AFTER SEVERALS ATTEMPTED. THE CONTACT STATED THE FAILURE OCCURRED INTERMITTENTLY. THE CHECK ENGINE WARNING LIGHT ILLUMINATED. THE CONTACT STATED THAT ON HIS WAY TO MCKENZIE BUICK-GMC DEALER, 6500 CAROLINE ST, MILTON, FL 32570, THE CHECK ENGINE WARNING LIGHT WAS NOT ILLUMINATED, THE VEHICLE WAS DIAGNOSED AND THE CONTACT WAS INFORMED THAT A FAILURE CODE WAS NOT FOUND. THE VEHICLE WAS NOT REPAIRED. HOWEVER, THE CONTACT CALLED BACK THE SAME DEALER AND INFORMED THEM THAT THE FAILURE RECURRED. THE VEHICLE WAS NOT YET TAKEN BACK TO THE DEALER. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 86.

ENGINE LIKE KEEPS COMING ON. CODE READING THE KNOCK SENSOR NEEDS TO BE REPAIR. SENSOR HAS BEEN REPLACE TWICE IN THE PAST THREE MONTHS. *TR

VEHICLE EQUIPPED WITH L87 6.2L. AT 197 MILES ENGINE SUDDENLY CEASED OPERATING AND WOULD NOT RESTART. THIS OCCURRED WHILE STOPPED ON PRIVATE ROAD. VEHICLE HAD TO BE TOWED TO DEALERSHIP WHERE THEY FOUND P0300 AND DIAGNOSED BROKEN #4 CYLINDER EXHAUST VALVE SPRING.

RUPTURED OIL COOLER LINE. DRAINING THE ENGINE OF OIL AND CAUSING LOCK-UP. *TR