2017 GMC Sierra

I HAVE A 2017 GMC SIERRA DENALI 1500. I BOUGHT IT NEW AND IT HAS VERY, VERY LOW MILEAGE. AT VARIOUS SPEEDS THERE IS A VIBRATION. FEELS LIKE I AM DRIVING OVER RUMBLE STRIPS. I HAVE ALWAYS NOTICED IT BUT MOSTLY THOUGHT IT WAS JUST SPOTS ON THE ROAD THAT WERE CAUSING IT. I STARTED TO DO A LITTLE RESEARCH AND LEARNED THAT THIS IS A KNOW ISSUE IN CHEVROLET AND GMC TRUCKS. NUMEROUS STORIES OF DEALERS IGNORING IT, COMPLAINTS ON MANY FORUMS, WHOLE WEBSITE DEDICATED TO IT, A NUMBER OF CLASS ACTION LAWSUITS, AND REPORTS TO THE NHTSA. LITERALLY THOUSANDS OF OWNERS ARE INVOLVED. GM HAS ISSUED A PRELIMINARY INVESTIGATION SERVICE BULLETIN (BULLETIN NO.: PI1354I), BUT DEALERS WANT TO CHARGE FOR DIAGNOSING AND POSSIBLY REPAIRING THIS MANUFACTURER'S DEFECT.

VEHICLE FREQUENTLY EXHIBITS LOSS OF BRAKING POWER. WHEN THIS OCCURS, SOMETHING SOUNDING LIKE THE ABS SYSTEMS IS SOMETIMES ENGAGED BY THE VEHICLE AND OTHER TIMES NOT. WHILE GM CLAIMS BRAKING PERFORMANCE MEETS FEDERAL STANDARDS, THE BRAKING POWER IS GREATLY REDUCED WHEN THE HYDRAULIC SYSTEM IS ENGAGED AND ALMOST NON-EXISTENT WHEN NEITHER VACUUM PUMP NOR THE HYDRAULIC SYSTEM FUNCTIONS. EVEN IF THE BRAKING PERFORMANCE MEETS FEDERAL STANDARDS, IT CREATES A DANGEROUS SITUATION WHEN THE DRIVER IS NOT EXPECTING A FAILURE. A GMC DEALERSHIP HAS ADMITTED THERE IS AN ISSUE AND RECOMMENDS REPLACING THE VACUUM PUMP BUT HAS BEEN UNABLE TO SOURCE THE PARTS IN OVER TWO WEEKS AND HAS NO ETA FOR WHEN THE PART WILL BE AVAILABLE. MEANWHILE THE BRAKING POWER LOSS CONDITION OCCURS EVERY TIME THE VEHICLE IS DRIVEN. DURING THE FIRST INSTANCE, I WAS TOWING A TRAVEL TRAILER IN STOP AND GO TRAFFIC DOWN A 7% GRADE. HAD IT NOT BEEN FOR THE TRAILER BRAKES, THIS COULD HAVE BEEN CATASTROPHIC. THE SECOND OCCURRENCE INVOLVED BACKING INTO MY DRIVEWAY AND NEARLY CAUSING A COLLISION BECAUSE OF POOR BRAKING PERFORMANCE. NOW THAT I FULLY AWARE OF THE ISSUE, THE VEHICLE IS DRIVEN SPARINGLY (ONLY WHEN ABSOLUTELY NEEDED) AND WITH GREAT CARE. THE CHARACTERIZATION OF THIS ISSUE BY GM AS NOT BEING A GRAVE SAFETY CONCERN IS INACCURATE. THEIR INABILITY TO SOURCE PARTS IN A TIMELY MANNER IS INEXCUSABLE.

WHILE OPERATING VEHICLE ON HIGHWAY, I EXPERIENCE A SHAKE/SHUDDER WHEN AT SPEEDS OF 50 MPH AND HIGHER. VEHICLE WAS TAKEN TO DEALER STATED THAT THE TORQUE CONVERTER DID SHUDDER. DEALER CHANGED TRANSMISSION FLUID AND I WAS ADVISED TO DRIVE FOR 200 MILES TO SEE IF PROBLEM WAS CORRECTED. SHUDDER STILL REMAINS AND NOW THE VIBRATION IS CONSTANT AT 70 MPH. I CALLED DEALER AGAIN WHO SAID THAT IT WAS PROBABLY A TIRE BALANCE ISSUE. I ARGUED WITH THEM AND STATED I HAD NO SUCH ISSUE BEFORE FIRST BRINGING VEHICLE IN. DEALER IS SETTING UP APPOINTMENT FOR ME TO TAKE IN AGAIN. VIBRATIONS HAVE LITERALLY CAUSED MY 6 YR OLD DAUGHTER TO VOMIT ON 3 DIFFERENT OCCASIONS WHEN IN THE VEHICLE. SHE HAS ONLY BEEN IN VEHICLE 5 OR 6 TIMES. VEHICLE FEELS UNSAFE AT HIGHWAY SPEEDS. I HAVE READ MANY FORUMS ONLINE STATING THIS ISSUE IS ON MANY VEHICLES GM HAS MADE. I AM CURIOUS AS TO WHEN GM WILL BE MANDATED TO TAKE CORRECTIVE ACTION OR BUY THE VEHICLES BACK FROM THE OWNERS.

THERE IS A SHUTTERING IN THE TRANSMISSION AS THE VEHICLE ATTEMPTS TO CLIMB SLIGHT/STEEP GRADES AT SLOW TO MEDIUM SPEEDS. AROUND 1500 RPM THE VIBRATION IS SENT THROUGHOUT THE WHOLE VEHICLE. HAVING TO INCREASE ACCELERATION TO ALLOW THE TRUCK TO SHIFT PROPERLY TO OVERCOME THE LACK OF POWER HAS CREATED A DANGEROUS SITUATION WHILE NAVIGATING UP SNOWY/ICE HILLS. THE VEHICLE ALSO PERFORMS A LURCHING OR SUDDEN SPEEDING UP WHEN DOWNSHIFTING WHEN SLOWING TO COME TO A STOP. DEPENDING ON ROAD CONDITIONS THIS CREATES A DANGEROUS SITUATION WHEN APPROACHING ICY/SLIPPERY INTERSECTIONS.

FIRST AND MOST IMPORTANTLY MY BRAKES ARE MY MAIN ISSUE AND SAFETY PROBLEM. I NEARLY RAN INTO THE CAR IN FRONT OF ME AT A BUSY INTERSECTION. MY TRUCKS BRAKES LOSE PRESSURE AFTER THE FIRST INITIAL STOP COMING TO ANY TRAFFIC LIGHTS, STOP SIGN, SLOW TRAFFIC, PARKING LOTS ETC... NO MATTER HOW SLOW OR FAST THE TRUCKS MOVEMENT IS. FIRST BREAK ATTEMPT IS OK BUT 2ND STARTS LOSING PRESSURE AND 3RD ATTEMPT IS COMPLETE LOST OF PRESSURE ANF AND THE TRUCK JUST ROLLS UNTIL IT SLOWLY COMES TO A STOP. I WORRY ABOUT THE SAFETY OF MYSELF AND OTHERS MOTORIST REGARDING THIS ISSUE. MY SECOND COMPLAINT IS MY DRIVER SIDE MIRROR. EVERY TIME I GET INTO MY TRUCK AND START IT. MY DRIVER SIDE MIRROR MOVES OUT OF ITS SETTING AND I CONSTANTLY HAVE TO FIX IT.

AFTER USING THE REMOTE STARTER WHILE VEHICLE WAS PARKED IN MY DRIVEWAY, I STARTED TO DRIVE MY GRANDSON TO SCHOOL. A SHORT DISTANCE FROM HOME SMOKE AND SPARKS STARTED TO EMIT FROM THE REAR SEAT NEXT TO THE SLIDING WINDOW AND ELECTRIC REAR WINDOW DEFROSTER. AS I PULLED OVER THE REAR WINDOW PANEL ON THE PASSENGER SIDE BURST. I ASSUME FROM EXCESSIVE HEAT GENERATED BY THE REAR WINDOW DEFROSTER.

MY 2017 GMC SIERRA SHUTTERS AND JERKS WHEN GOING INTO AND OUT OF 1ST GEAR AND GOING AROUND CORNERS WHEN IT CHANGES GEARS. ESPECIALLY WHEN COLD. DOES NOT HAPPEN ALL THE TIME. AT TIMES IT HAS JERKED INTO AN INTERSECTIONAND WAS SCRY. MY WIFE WILL NOT DRIVE THIS VEHICLE. HAVE HAD IT LOOKED AT NUMEROUS TIMES AND THEY HAVE CHANGED THE FLUID. THEY TELL ME I HAVE A QUIRKY TRANS OR IT IS INHERENT TO THIS TRANSMISSION. IT IS EXTREMELY FRUSTRATING AND SCARY AT TIMES. I DON'T KNOW WHAT TO DO TO GET GM TO FIX IT. THIS HAS BEEN GOING ON SINCE I PURCHASED THE TRUCK ON 10/31/2017.