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.

- Shenandoah, TX, USA

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.

- Panorama City, CA, USA

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.

- Somerset, KY, USA

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

- Kenosha, WI, USA

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

- Winchester, VA, USA

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.

- Charlotte, NC, USA

Engine knock on 6.2 liter engine. When the vehicle sits a knocking occurs in the engine upon startup. It is not a lifter knock, but a knock deeper in the engine GM has noted the problem and made multiple repairs (6+) cam shaft changed but no lifters. Thought this was odd as the wearing surfaces are now dissimilar.GM said this is all they authorized. Knock still present GM then removed upper end of engine. Noted extreme carbon build up on multiple pistons. One piston had so much building apparently close to valves hitting. GM tech advised engine replacement, GM authorized cleaning of pistons: Guess what, knock still present the knocking is a piston or lower end knock. Similar to wrist pins or rod bearing caps or bearings. When knocking occurs engine is rough and pulsates. Time ranges from 30 seconds to couple of minutes after multiple GM repairs knock is still present, noticed engine performance is not the same and with lack of stability fuel economy has dropped

- Woodland Hills, CA, USA

The car had an oil pump failure in July (zero oil pressure in the engine), after which it was towed to an independent shop who is currently replacing the oil pump and verifying that no damage was done to the engine for a cost of about $2000. Upon investigation on my part, GM has known that oil pumps can fail on not only my car but any car with a "generation 4" V8 including a 6th generation Corvettes. They have released to their dealers document pip4158G stating this. I think personally that this is a safety issue and there should be a recall, but at the very least GM should have to pay for any service work done because of this "known" issue. I refuse to take my car to a GM dealer, due to the past treatment of my car by dealers (they are careless) and so GM will do nothing as they say "it can't be diagnosed by anyone but a GM dealer." That's hogwash

- Troy, MI, USA

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.

- Louisville, KY, USA

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

- Sunnyvale, CA, USA

Driving normal citystreets 25mph when engine noise started, went another 2 blocks, engine stopped running, towed to Chevy dealer. If this had happened on major highway, possible catastrophic effects.no power steering, brakes, engine oil on roadway, steering wheel lock, wrecks, injuries or possible fatalities. Engine head poor workmanship in these LS7 engines.

- Granite City, IL, USA

This is the second time the engine has stalled while she was driving. The first time the vehicle was only going about 5 mph. The second time it was gong 35 mph. The car will restart. No malfunction were detected by an obd 2 tester. No computer malf. Indications no ck eng lights. The car now is completely dead in the garage. Requires towing. Battery is only 2 to 3 months old.

- Templeton, CA, USA

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, loosing a valve while driving will result in loss of power assist for steering and breaking while on the road. I took my car with 13500 miles on it to a Corvette specialty shop to have my valve guide clearance tested. I had (8) exhaust valve guide and (3) intake valve guides outside of service specifications, and a combination of (5) other intake 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. I can provide data on the failed guides for documentation 88% of the Corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: 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.

- Kenosha, WI, USA

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.

- Alta, CA, USA

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.

- Oakhurst, CA, USA

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.

- Katy, TX, USA

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.

- Jones, OK, USA

Engine started making noise, feeling there could be a failure I drove to my servicing Chevrolet dealer. They listened to the engine and said, that's normal. Not trusting that judgment, I had an independent shop inspect the engine, and had the valve issue resolved at my expense. I was still under extended warranty, which made me angry. But if the dealer says there is noting wrong, what am I supposed to do" after the repair was performed at my expense, I took the failing parts back to the dealer for them to inspect. They admitted they were wrong, but what good did that do me" keep in mind my vehicle had less than 10K miles on it. This is where I feel safety comes into play; had my engine failed and locked up on todays crowed interstates, I could have caused a major accident. The failures I have read about, gave no warning, when the engine let-go.

- Chehalis, WA, USA

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!

- Atascadero, CA, USA

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. 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.

- Naples, FL, USA