2008 CHEVROLET CORVETTE Z06 Engine Problems

The contact owns a 2008 Chevrolet Corvette. The contact stated that while driving out of his driveway, the "Service Active Handling System" warning light was illuminated. Neither the dealer nor an independent mechanic was made aware of the failure. The vehicle was not diagnosed nor repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 75,600.

Mileage: 75,600

2008 CORVETTE C6 Z06. CONSUMER WRITES IN REGARDS TO VALVE GUIDE MACHINING ISSUES. *LD *JS

LOUD TICKING COMING FROM VALVES, WORRIED TO DROP A VALVE WHEN DRIVING

Mileage: 30,000

DEFECTIVE VALVE GUIDES. THIS FIRST HAPPENED AT 13,500 MILES, AND CHEVROLET DID REPLACE THE HEADS UNDER WARRANTY. NOW IT HAS HAPPENED AGAIN AT 28500 MILES AND I HAVE SPENT OVER $3100 IN PARTS ALONE TO FIX THE PROBLEM, WHICH HAS BEEN VERIFIED BY THE COMPANY WHO SOLD ME THE REPLACEMENT HEADS. I PROVIDED THE LABOR OR THE COST WOULD HAVE BEEN $1700 HIGHER. FOUR INTAKE VALVE GUIDES WERE BEYOND THE CHEVROLET REPLACEMENT SPEC AND ANOTHER FOUR WERE ALREADY AT THE CHEVROLET SERVICE LIMIT WITH ONLY 15000 MILES ON THE REPLACEMENT HEADS. OBVIOUSLY THE PROBLEM OCCURRED DURING CITY AND HIGHWAY DRIVING.

Mileage: 28,500

I BOUGHT MY 2008 Z06 BACK IN DECEMBER 2016 WITH 27000 MILES ON IT. LOVE THE CAR BUT FROM I UNDERSTAND READING ABOUT THE COMPLAINS FROM OTHER OWNERS IT HAS VALVE PROBLEMS AND THE CAN GIVE AWAY AT ANY TIME. DEAR GM I DON'T CARE HOW YOU TAKE THIS, BUT SHOULD MY 2008 LS7 MOTOR BREAK DOWN DUE TO THIS SPECIFIC SITUATION YOU WILL FIX IT AT YOUR OWN COST, I AM PRINTING THE COMPLAINS FROM THE FORUM ABOUT THE LS7 MOTOR ISSUES, AND IF THAT EVER HAPPENS TO MY CAR AND YOU REFUSE TO FIX IT, TV STATIONS, RADIO STATIONS, AND NEWS PAPERS WILL KNOW ABOUT THIS. LET ME CLEAR THIS IS A STATEMENT I AM MAKING THANK YOU

ENGINE IS MAKING A LOUD TICKING NOISE. SHOP RECOMMENDED TO REPLACE VALVE GUIDES AND REMACHINE CYLINDER HEADS. THIS IS TO PREVENT A VALVE DROPPING INTO THE ENGINE DUE TO OUT OF SPEC CYLINDER HEADS FROM THE OEM SUPPLIER. THIS IS A HIGH OCCURRENCE PROBLEM THAT HAS LOW OR REMOTE DETECTION METHODS. THE SEVERITY PRESENTS A POTENTIAL SAFETY/FIRE HAZARD.

Mileage: 46,011

I WAS CONCERNED ABOUT EXCESSIVE VALVE TRAIN NOISE AND AFTER READING SEVERAL CORVETTE FORUM THREADS ABOUT IMPROPERLY MACHINED HEADS BY GM'S SUPPLIER LINAMAR, AND THAT NUMEROUS VEHICLES HAVE HAD VALVES DROP AND RUIN THE ENGINES, I TOOK MY CAR WITH 9500 MILES ON IT TO A CORVETTE SPECIALTY SHOP TO HAVE MY VALVE GUIDE CLEARANCE TESTED. I HAD (2) INTAKE VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, (4) EXHAUST VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, AND A COMBINATION OF (10) OTHER INTAKE AND EXHAUST VALVE GUIDES AT OR NEAR THE MAXIMUM OUTSIDE OF SERVICE SPECIFICATIONS. THE CAR IS BEING REPAIRED WITH PROPER RE-MACHINING OF THE HEADS TO MAKE THE VALVE GUIDES CONCENTRIC, NEW INTAKE AND EXHAUST VALVE GUIDES INSTALLED, AS WELL AS NEW SEALS, VALVES, SPRINGS, ETC. 88% OF THE CORVETTE FORUM MEMBERS WHO HAVE HAD THEIR CYLINDER HEADS TESTED FOR EXCESSIVE VALVE GUIDE WEAR, WERE OUT OF SERVICE SPECIFICATIONS. SOURCE: HTTP://WWW.CORVETTEFORUM.COM/FORUMS/...-REGISTRY.HTML GM NEEDS TO ISSUE A RECALL ON THIS ISSUE, THERE HAVE BEEN NUMEROUS ENGINE FAILURES AS A RESULT OF A DROPPED VALVE INTO A CYLINDER WHICH CAN CAUSE ACCIDENTS AND FIRES. GM IS VERY AWARE OF THIS ISSUE, BUT REFUSES TO DO ANYTHING ABOUT THIS HUGE SAFETY RISK TO DRIVERS, PASSENGERS, AND NEARBY VEHICLES IF THE ENGINE FAILS GOING DOWN THE ROAD.

Mileage: 9,500

THE 7L 427 ENGINE HAS A VALVE FAILURE PROBLEM. THE VALVE HEADS BREAK OFF INSIDE THE ENGINE WHILE RUNNING. THIS HAPPENED TO ME AS I WAS DRIVING ALONG A HIGHWAY AT 60 MILES PER HOUR NOT ACCELERATING BRAKING OR TURNING, IN A VERY REMOTE PART OF TEXAS. THE ENGINE SEIZED UP. THIS IS A KNOWN ISSUE BY GM WITH A MUCH HIGHER THAN EXPECTED FAILURE RATE YET HAS NEVER HAD A SERVICE BULLETIN NOR RECALL. THE CAR HAD 18,000 MILES ON IT AT THE TIME AND HAD NEVER BEEN TO THE TRACK OR ABUSED IN ANY WAY. OIL WAS CHANGED AT 3,000 MILE INTERVALS BY A CERTIFIED SHOP. BETWEEN TOWING AND REPAIR THE TOTAL BILL WAS OVER $ 16,000. BECAUSE THE CAR HAD BEEN IN SERVICE OVER 5 YEARS DESPITE THE LOW MILEAGE, GM PICKED UP ONLY 45% OF THE COSTS LEAVING ME WITH OVER A $ 10,000 BILL. THIS IS A HIGH PERFORMANCE VERY EXPENSIVE SPORTS CAR THAT HAD A COMPLETE ENGINE FAILURE AT 18,000 MILES. *TR

Mileage: 18,000

YES ,WHEN DRIVING THE CORVETTE ON THE HIGHWAY AND THE ENGINE BLEW UP AND QUIT WORKING EVERYTHING POTENTIALLY CAUSING AN ACCIDENT TO ME AT THAT TIME I WAS VERY SCARED.........THE VALVE DROPPED THROUGH THE 8TH CYLINDER,WHILE DRIVING ALMOST CAUSING DRIVERS TO CRASH. *TR

Mileage: 34,795

VEHICLE IS COMPLETELY STOCK WITH ONLY 18,000 MILES ON IT. IT HAS NEVER BEEN ON A TRACK OR USED FOR ANYTHING OTHER THAN A WEEKEND TOY. COMPLETE ENGINE FAILURE AS A RESULT OF A VALVE BREAKING OFF INSIDE THE ENGINE WHILE DRIVING CASUALLY AT 50 MPH. AS A RESULT THE ENGINE STOPPED RUNNING TAKING WITH IT THE POWER STEERING AND POWER ASSISTED BRAKES. I WAS ON A COUNTRY ROAD APPROXIMATELY 45 MILES FROM THE NEAREST GAS STATION OR SERVICE FACILITY OF ANY KIND. THERE WAS ALSO NO CELL PHONE SERVICE AND WAS LEFT STRANDED. I HAVE SINCE HAD A BRAND NEW ENGINE PUT IN AT A TOTAL COST OF OVER $ 16,000.

Mileage: 18,000

RECENTLY MY LOW BEAM HEADLIGHTS WOULD RANDOMLY STOP WORKING. AT FIRST THEY WOULD GO OFF AND COME BACK ON AFTER A COUPLE MINUTES BUT NOW I'L BE LUCKY IF THEY TURN ON AT ALL. THE PROBLEM COMES FROM THE FUSE BOX LOCATED UNDER THE HOOD. IN THE BEGINNING I WOULD GET OUT OF MY CAR AND PLAY AROUND WITH THE LOW BEAM RELAY UNTIL THE LIGHTS CAME ON AND STAYED ON BUT NOW THAT DOES NOT EVEN HELP. ITS OBVIOUSLY A PROBLEM DUE TO THE FUSE BOX. I KNOW THERE ARE MANY OTHER CORVETTE OWNERS WHO HAVE THE SAME ISSUE. I HOPE GM WILL FIX THIS PROBLEM.

Mileage: 70,500

ENGINE VALVES NOISY AND SHOWED EXCESSIVE WEAR AT 17,000 MILES. CONCERNS THAT THE ENGINE COULD FAIL WHILE THE VEHICLE IS IN MOTION, RENDERING POWER STEERING AND POWER BRAKES INOPERABLE, RISKING A CRASH. HAD CYLINDER HEADS REPLACED AS A PRECAUTION TO PREVENT A POTENTIAL DROPPED VALVE.

Mileage: 17,200

HAD TO HAVE THE HEADS REWORKED BECAUSE OF BAD GUIDES AT 13,500 MILES. CAR OUT OF WARRANTY GM DOES NOTHING AND CLAIMS THERE ISN'T A PROBLEM. STOCK 2008 Z06 WITH 13,500 MILES ALL (8) EXHAUST OUT OF SPEC, (3) INTAKE OUT OF SPEC (5) INTAKE ONLY IN SPEC BY .0001-.0004 MEASUREMENT DONE BY KATECH/WCCH CAN PROVIDE DATA IF NEEDED

Mileage: 13,500

VALVE GUIDES ON HEADS WERE OUT OF SEPCIFICATION AND WIGGLED VISIBLY WITH SLIGHT SIDE PRESSURE, EVEN WHEN LOADED. HEADS R&R'D AT A COST OF $2500

Mileage: 47,000

ENGINE DROPPED EXHAUST VALVE WHILE THE ENGINE WAS TURNING 6800 RPM IN THIRD GEAR AT 118 MPH. THE ENGINE STOPPED RIGHT AT THE TIME I WENT TO SHIFT TO 4TH GEAR AND THE TACH DROPPED TO ZERO. I PULLED THE CAR INTO A RUN OFF AREA AND GOT OUT OF THE CAR BECAUSE I THOUGHT IT MIGHT BE ON FIRE DUE TO ALL OF THE SMOKE.

Mileage: 24,000

I HAD TO REPLACE THE EXHAUST VALVES IN MY 2008 Z06 IN ORDER TO PREVENT CATASTROPHIC FAILURE. REPLACED 2-PIECE SODA FILLED VALVES WITH 1 PIECE STAINLESS STEEL VALVES. UPON INSPECTION VALVE GUIDES ON #3 HAD EXCESS SLOP. SENT HEADS OUT FOR MACHINING AND NEW GUIDES. STOCK ENGINE HAD LESS THAN 20K MILES. MANUFACTURER OF ENGINE HAS ISSUED SERVICE BULLETINS ACKNOWLEDGING THESE ERRORS EXIST.

Mileage: 18,200

THE LS7 ENGINE HAS A DEFECT THAT CAUSES ACCELERATED VALVE GUIDE WEAR. CONTINUING TO DRIVE THE CAR WILL EVENTUALLY LEAD TO A VALVE DROPPING AND CAUSING CATASTROPHIC ENGINE FAILURE. ONCE THIS OCCURS THERE WILL BE A LOSS OF POWER STEERING, POWER BRAKES, AND WATER/OIL COULD GET ON THE TIRES LEADING TO A LOSS OF CONTROL OF THE CAR. IN A FEW CASES FIRE HAS ERUPTED. HERE ARE TWO VIDEOS OF THE ISSUE HAPPENING: HTTPS://WWW.YOUTUBE.COM/WATCH?V=TM4MDCIX-KI HTTPS://WWW.YOUTUBE.COM/WATCH?V=ZLT7DJNKVNY LUCKILY I FOUND THE EXCESSIVE VALVE GUIDE WEAR BEFORE THE ENGINE FAILED, BUT IT COST ME $3000 TO HAVE THE HEADS REBUILT. UPDATED 09/15/15*LJ *CN

Mileage: 14,923

I WAS CONCERNED ABOUT EXCESSIVE VALVE TRAIN NOISE AND AFTER READING SEVERAL CORVETTE FORUM THREADS ABOUT IMPROPERLY MACHINED HEADS BY GM'S SUPPLIER LINAMAR, AND THAT NUMEROUS VEHICLES HAVE HAD VALVES DROP AND RUIN THE ENGINES, I TOOK MY CAR WITH 40000 MILES ON IT TO A CHEVROLET DEALER TO HAVE MY VALVE GUIDE CLEARANCE TESTED. I HAD INTAKE VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, EXHAUST VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, AND A COMBINATION OF OTHER INTAKE AND EXHAUST VALVE GUIDES AT OR NEAR THE MAXIMUM OUTSIDE OF SERVICE SPECIFICATIONS. THE CAR IS BEING REPAIRED WITH NEW HEADS AND GUIDES. GM NEEDS TO ISSUE A RECALL ON THIS ISSUE, THERE HAVE BEEN NUMEROUS ENGINE FAILURES AS A RESULT OF A DROPPED VALVE INTO A CYLINDER WHICH CAN CAUSE ACCIDENTS AND FIRES. GM IS VERY AWARE OF THIS ISSUE, BUT REFUSES TO DO ANYTHING ABOUT THIS HUGE SAFETY RISK TO DRIVERS, PASSENGERS, AND NEARBY VEHICLES IF THE ENGINE FAILS GOING DOWN THE ROAD. *TR

Mileage: 40,000

DURING MODERATE ACCELERATION AND MID RANGE RPMS, THE ENGINE CATASTROPHICALLY FAILED ON THE HIGHWAY. A HOLE WAS BLOWN IN THE ENGINE BLOCK AND THE CAR SPEWED SMOKE, OIL AND CHUNKS OF METAL FROM THE ENGINE ALL OVER THE ROAD AS I VEERED OFF ONTO THE SHOULDER. THE SUSPECTED ISSUE WAS FAULTY HEADS AND IMPROPERLY MACHINED VALUE GUIDES. THIS ENGINE WAS REPLACED UNDER WARRANTY. THE SECOND ENGINE HAD AN ISSUE WITH THE CLEARANCE BETWEEN THE CRANKSHAFT AND THE PISTON ARM. AFTER APPROXIMATELY 4500 MILES ON THE SECOND ENGINE, THE CAR LOCKED UP AND DIED IN THE MIDDLE OF TRAFFIC CAUSING A MASSIVE TRAFFIC JAM FOR ABOUT HALF AN HOUR. I HAD TO PUSH THE CAR BY HAND IN TRAFFIC TO THE FARTHEST EDGE OF THE RIGHT HAND LANE SINCE THERE WAS NO SHOULDER. AFTER THE CAR COOLED DOWN FOR HALF AN HOUR I WAS ABLE START THE VEHICLE AND MAKE IT TO A DEALER. THIS ENGINE WAS ALSO REPLACED UNDER WARRANTY. *JS

Mileage: 28,000

CHECKED ENGINE HEADS AND VALVES DUE TO THE ONGOING ENGINE FAILURES OF THE LS7 ENGINE. NUMBER 7 INLET VALVE WAS FOUND TO BE STRESSED TO THE POINT OF IMMINENT FAILURE DUE TO THE FACTORY MACHINING BEING OUT OF ALIGNMENT WITH THE VALVE STEM AND THE VALVE SEAT. 2 OTHER INLET VALVES WERE FOUND NOT CONCENTRIC AND WERE REPLACED ALSO. THE EXHAUST VALVES WERE FOUND TO BE OUT OF FACTORY SPECIFICATIONS WITH THE VALVE GUIDES SO ALL 16 VALVE GUIDES AND 8 EXHAUST VALVES WERE REPLACED ALSO AND THE HEADS MACHINED TO FACTORY SPECIFICATIONS. WHEN THESE ENGINES FAIL, THE ENGINE STOPS AND YOU HAVE NO POWER STEERING OR VACUUM POWER TO THE BRAKES SO YOU STRUGGLE TO STOP THE CAR AND STEER IT TO A SAFE PLACE. THE ENGINE BLOCK, BEING ALUMINUM, NORMALLY VENTILATES WITH A CONROD OUT THE SIDE AND OIL AND COOLANT IS DEPOSITED ON THE ROAD SURFACE. NOT A GOOD SITUATION IN MY OPINION AS WE DRIVE OUR CAR ON MAJOR HIGHWAYS FAIRLY REGULARLY. GENERAL MOTORS IS AWARE OF THE SITUATION AND SO FAR HAS DONE NOTHING TO SHOW ANY CONCERN FOR THE MOTORIST WHO OWNS THE CAR OR THE INNOCENT MOTORIST MINDING HIS/HER OWN BUSINESS ON THE HIGHWAY. *TR

Mileage: 42,000

HAD MY VALVES CHECKED TO SEE IF THEY WERE OUT OF SPEC. I HAVE ATLEAST THREE EXHAUST VALVES THAT ARE OUT OF SPEC. AND I'M AFRAID TO EVEN DRIVE THE CAR FOR FEAR OF DROPPING A VALVE IN THE MOTOR, THUS POTENTIALLY CAUSING OIL OR ANTIFREEZE TO LEAK AND GET UNDER MY TIRES CAUSING ME TO WRECK MY $60,000 CAR, OR CAUSE HARM TO MYSELF OR TO OTHER DRIVERS. THIS IS A BIG SAFETY ISSUE FOR ME AND OTHER DRIVERS, NOT TO MENTION THE COST OF REPLACING THE MOTOR. *TR

Mileage: 72,000

CONCERNED ABOUT THE NUMBER OF DROPPED VALVES IN THE LS7 ENGINE USED IN THE CORVETTE Z06 THAT MAY RESULT IN A BLOWN ENGINE CAUSING A CRASH OR FIRE. I HAVE PRETTY MUCH PARKED MY 2008 Z06 DUE TO THIS CONCERN AS GM REFUSES TO ACKNOWLEDGE THAT THERE IS A PROBLEM BUT EMPIRICAL EVIDENCE ON PUBLIC USER FORUMS SHOWS THAT THERE IS A PROBLEM AND GM SHOULD ADDRESS AND FIX. I URGE THE NHTSA TO LOOK INTO THIS MATTER AS A MAJOR SAFETY CONCERN! *TR

I WAS CONCERNED ABOUT EXCESSIVE VALVE TRAIN NOISE AND AFTER READING SEVERAL CORVETTE FORUM THREADS ABOUT IMPROPERLY MACHINED HEADS BY GM'S SUPPLIER LINAMAR, AND THAT NUMEROUS VEHICLES HAVE HAD VALVES DROP AND RUIN THE ENGINES, I TOOK MY CAR WITH 27000 MILES ON IT TO A CORVETTE SPECIALTY SHOP TO HAVE MY VALVE GUIDE CLEARANCE TESTED. I HAD (2) INTAKE VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, (4) EXHAUST VALVE GUIDES OUTSIDE OF SERVICE SPECIFICATIONS, AND A COMBINATION OF (10) OTHER INTAKE AND EXHAUST VALVE GUIDES AT OR NEAR THE MAXIMUM OUTSIDE OF SERVICE SPECIFICATIONS. THE CAR IS BEING REPAIRED WITH PROPER RE-MACHINING OF THE HEADS TO MAKE THE VALVE GUIDES CONCENTRIC, NEW INTAKE AND EXHAUST VALVE GUIDES INSTALLED, AS WELL AS NEW SEALS, VALVES, SPRINGS, ETC. 88% OF THE CORVETTE FORUM MEMBERS WHO HAVE HAD THEIR CYLINDER HEADS TESTED FOR EXCESSIVE VALVE GUIDE WEAR, WERE OUT OF SERVICE SPECIFICATIONS. SOURCE: HTTP://WWW.CORVETTEFORUM.COM/FORUMS/C6-Z06-DISCUSSION/3386141-THE-OUT-OF-SPEC-GUIDE-WEAR-REGISTRY.HTML GM NEEDS TO ISSUE A RECALL ON THIS ISSUE, THERE HAVE BEEN NUMEROUS ENGINE FAILURES AS A RESULT OF A DROPPED VALVE INTO A CYLINDER WHICH CAN CAUSE ACCIDENTS AND FIRES. GM IS VERY AWARE OF THIS ISSUE, BUT REFUSES TO DO ANYTHING ABOUT THIS HUGE SAFETY RISK TO DRIVERS, PASSENGERS, AND NEARBY VEHICLES IF THE ENGINE FAILS GOING DOWN THE ROAD.

Mileage: 27,000

I WOULD LIKE TO FILE A COMPLAINT DUE TO SAFETY CONCERNS OVER BAD HEADS AND VALVES PUT INTO A PERCENTAGE OF THESE CORVETTE Z06 CARS. GM HAS ADMITTED THERE IS AN ISSUE AND YET REFUSES TO DO ANYTHING ABOUT IT. THERE WAS A MACHINING ERROR WITH THESE HEADS AND THE ENGINES CAN DROP A VALVE WITHOUT WARNING OR SYMPTOMS AND WITHOUT PULLING YOUR MOTOR APART THERE IS NO WAY TO DETERMINE IF YOUR CAR IS AFFECTED OR NOT. THE FACT IS NOW THAT AN INCREASING PERCENTAGE OF THESE CARS ARE LOSING THEIR ENGINES AND REPLACEMENT COST IS OVER 17000.00. SHOULD THE ENGINE GO IT COULD LEAD TO A SERIOUS CRASH FROM THE ROD PUNCTURING THE BLOCK AND SPREADING OIL UNDER AND AROUND THE CAR WHICH NOT ONLY AFFECTS THE CAR IN QUESTION BUT ANY OTHERS FOLLOWING IT AT HIGHWAY SPEED. THERE HAVE BEEN SOME THAT HAVE GONE OFF THE ROAD BECAUSE OF THIS ISSUE AND IT IS TAKING ANY OF THE JOY OF OWNING OR DRIVING THIS CAR AT ALL. GM WILL NOT EVEN TELL ANYONE OUT OF WARRANTY WHAT TO DO TO ADDRESS THE PROBLEM AND WHEN SOME HEADS WERE REPLACED BY GM FOR CARS UNDER WARRANTY, SOME WERE FOUND TO HAVE BAD TOLERANCES BEFORE EVEN BEING INSTALLED. GM HAS NOW GONE ON TO THEIR NEW MODEL Z06 AND IS SIMPLY HOPING THIS ISSUE GOES AWAY WHILE THROWING ALL THEIR LOYAL CUSTOMERS UNDER THE BUS SO TO SPEAK. SOMETHING SHOULD BE DONE BEFORE THERE IS A DEATH CAUSE FROM THIS ISSUE, NOT TO MENTION A LOYAL CUSTOMER LOSING A 17000. ENGINE THROUGH NO FAULT OF THEIR OWN. I HAVE CONTACT CHEVROLET SEVERAL TIMES AND WAS MET WITH LITTLE RESPONSE OR ENTHUSIASM TO DO ANYTHING ABOUT THE PROBLEM AT ALL.

Mileage: 8,100

VEHICLE TAKEN TO DEALER FOR EXCESSIVE VALVE NOISE. INSPECTION SHOWED EXCESSIVE WEAR OF VALVES AND VALVE GUIDES...OUT OF SPECS. ENGINE HEADS AND VALVES TO BE REPLACED UNDER WARRANTY. *TR

Mileage: 18,000