#1 azdanz06's avatarazdanz06, 01-06-2015 11:27 am link to file complaint: Https://www-ODI.NHTSA.dot.gov/vehicl...nt/index.xhtml I just filed a complaint with the NHTSA about the out of spec valve guide issue, I would encourage everyone else to do so as well, maybe just maybe it will force GM to finally do a recall and qc on parts. Here is my complaint: 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, 88% of the corvette forum members who have had their cylinder heads tested for excessive valve guide wear, were out of service specifications. Source: Https://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. #2 whis9's avatarwhis9, 01-06-2015 11:39

- Cedar Park, TX, USA

Needle bearings were found in oil pan. This is very common problems in GM vehicles as defective uncaged rocker arm design which causes rocker arms to easily break off bearings. GM even issues a bulletin, but owners have to bear the cost of defective factory-parts. Broken needle bearings could end up in engine and destroy engine. Even owners replace broken rocker arms, they will fail because they're uncaged. To repair permanently, owners have to install caged rocker arms from non-factory part, which will nullify warranty. Owners are trapped in keep replacing rocker arms, or install non-defective non-factory caged rocker arms and lose warranty. GM should recall this problem.

- Centreville, VA, USA

The contact owns a 2007 Chevrolet Corvette. The contact stated that the check engine warning indicator illuminated when the vehicle was started. The contact stated that the vehicle had been at the dealer five other times for the same warning indicator. Various components were repaired, but the failure recurred. The vehicle was at the contact's residence awaiting an appointment date. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 67,000...updated 07/31/17

- Montarey, CA, USA

Valve broke and locked up engine. Car skidded off highway and was destroyed. I was driving on interstate and it was raining. No indication of problem before event

- Huntsville, AL, USA

While passing a large truck on a rural highway (fm 2004) the engine dropped a valve which as I have been informed is a known issue on these cars with the Z06 LS7 engine having premature valve guide wear. The motor locked up after the piston hit the valve resulting in catastrophic engine damage causing the rear tires to lock up as a result of the engine locking. I was able to apply the clutch and regain control of the car and there was no accident other than a close call with the 18 wheeler I was trying to pass. There are numerous instances of the same issues I have seen while researching with this car from 2007 to 2013 7.0 liter engine from GM.

- Alvin, TX, USA

2007 Chevrolet Corvette Z06 with LS7 engine - excessive engine valve guide wear - per the GM valve wiggle test my car was found to have up to 3 times the acceptable engine valve to guide clearance at 24,139 miles. Some LS7 engines have had this issue, breaking a valve due to the excessive clearance causing the engine block to break open, spilling oil onto the rear tires while in forward motion causing a serious safety concern. Due to the safety concern the engine was disassembled and repaired. GM has known of this issue and replaced many LS7 engines which did explode due to the valve guide wear issue.

- Muscle Shoals, AL, USA

Making a left turn in a stoplight inter-section the motor failed shutting off all power to the vehicle...motor failed due to excessive valve guide wear...vehicle was in motion on a city street

- Brookfield, WI, USA

I have a 2007 Corvette Z06 with 43 K miles on it. I decided to have someone check my car because of the article I had read about the LS7 engines having valve guide issues. I was sure that they would be ok because the Corvette sites say it is only a minor amount of heads that were machined in correctly. I was having other work done to my Corvette so looked for a place that does mostly Corvette service, I told the mechanic to check my valve guides while he was doing the other work I was sure they would of been ok. Upon my surprise he sent me videos showing me that they were not ok and needed to be repaired. It cost me $1,950 to have my heads cnc and new valve guides and springs installed the old ones were very bad I have videos showing this, the car was running with little valve noise at the time but were still bad mechanic would not even dyno the car after seeing how bad they were.

- Hillsbourgh, NJ, 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 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: 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.

- Federal Way, WA, USA

I've read several different posts about people with 2007 corvettes having problems with valves and dropping valves and losing control when this because of the power steering and brakes not working when this happens. I bought my 2007 Corvette Z06 new back in 2007 and I've always noticed valve noise and lately it seems a little louder. I hear the valve noise mostly driving it in town. I'm not sure if I should just wait for the valves to fail and take my chances or pay to have someone to pull the heads and check all the valves and repair any ones that are out of specification. So I think it's GM's responsibility to do a recall for this because in my opinion this is a defect and it would be very dangerous to drop a valve and lose control of my car. I spent a lot of money on this car and I just don't feel I should need to pay anymore money to diagnose and fix this problem. My headlights stopped working tonight and luckily there is a recall for that problem.

- Bonita, CA, USA

The exhaust valve broke off, and engine blew up. I was driving on highway.

- Clifton, NJ, USA

The contact owns a 2007 Chevrolet Corvette. While driving 45 mph, the vehicle made an abnormal noise coming from the roof panel. In addition, after a routine inspection, the technician diagnosed that the vehicle had an oil leak. The vehicle was not diagnosed or repaired. The VIN was excluded from NHTSA campaign number: 09V491000 (structure). The manufacturer was notified of the failure. The failure mileage was approximately 27,000.

- Raleigh, NC, USA

I am extremely 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 causing a loss of control of the vehicle due to the engine stopping abruptly. 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/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 severe 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. It has been noted on the forum that GM is very aware of the issues and I assume they think no one will report them for not handling it correctly. The issue is this is a critical safety issue for anyone driving a 06-13 Z06 model on the road. I am to the point I don't feel safe to drive my vehicle anymore due to the loud 'ticking' valve-train as it is (symptom) meaning it is likely to fail at any moment seizing the engine while on the road. I have waited on GM for 6 years to do the correct thing on their own but I am now reporting it due to their gross negligence and disregard of their customers safety.

- Powder Springs, GA, USA

Valves of specifications. I had to pay out of pocket to get this fixed. If I would have dropped a valve while driving I could have loss control of my car. This is a known problem that Chevrolet refuses to acknowledge 2007 Z06 23884 miles 1 int.008" #1 exh.006" #3 int.0085" #3 exh.005" #5 int.0085" #5 exh.010" #7 int.009" #7 exh.005" #2 int.010" #2 exh.011" #4 int.010" #4 exh.012" #6 int.008" #6 exh.017" #8 int.007" #8 exh.006" max GM spec is.0037" which would roughly be.0075" on the wiggle test. So basiclly if the wiggle test is over.0075" the guides are out of spec.

- Phenix City, AL, USA

The contact owns a 2007 Chevrolet Corvette. While driving approximately 50 mph, the contact applied the clutch to shift from second to third gear. When the clutch was released, the vehicle jerked as if the brakes were applied and the engine stalled. The contact engaged the clutch and maneuvered to the emergency lane. The contact was unable to restart the engine. The vehicle was towed to the dealer where it was discovered that a valve had fallen into cylinder one. As a result, the piston and cylinder wall were fractured. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 32,500.

- Hilmar, CA, USA

While driving the Corvette, the engine shut down with no notice. The dash indicated the vehicle had entered accessory mode. Power steering, power brakes and engine power were completely gone. Within a few seconds, the dic went from 'accessory mode' to 'shift into park'. in order to do so, I had to coast to a safe place. Once I got to a spot where I could move off the road, I shifted to park and restarted the car. It then drove on as usual, but there was no check engine light or other indicator. This happened only once this day, however occurred three additional times within 10 miles on the 23rd of July. I contacted a GM service technician who works at a Chevrolet dealership and he checked for any service bulletins or recalls. There were none for the Corvette. I searched the internet, and Corvette forum (I am a 10 year forum member). I found numerous instances of the ignition switch in 2005-2007 Corvettes failing in this manner. I located an ignition switch and replaced it. This fixed the problem in 15 minutes and for less than $50 at dealer retail. I know from other nhstc recalls on vehicles that ignition switch failures are considered a critical and dangerous failure. The failures in the Corvettes should be included in these recalls. If such a failure occurred during crossing traffic or while driving in close proximity interstate traffic, the results could easily be (and may already have been) deadly. Please consider initiating a recall, or including the affected years of Corvette in an existing recall. My car is now fixed due to my ability to search forums and other web based information, however most Corvette owners are not as involved or as web savvy and could be involved in a long drawn out problem/diagnosis process which would put their lives at risk. Thank you.

- Lavonia, GA, USA

While driving on the road at aprox. 45mph, my car exhaust valve dropped in the motor causing immediate engine failure also creating power steering and power brakes to stop working immediately. This same exhaust valve issues occurred with many other GM corvettes with the 7.0liter Z06 motor.

- Washington, DC, USA

Valve train rocker arms broken leaving needle bearings in the oil, and all valve guides were out of tolerance.

- Calhan, CO, USA

After months of reading about the exhaust valve issue with Corvette Z06S I took my car and had the heads checked. The shop found the valve guide clearance to be outside the specified acceptable range. The defect puts undue stress on the sodium filled valves and if the valve fails it can cause catastrophic engine damage and potentially deadly situation if this occurs at speed on the roadway as the driver will lose ability to control the vehicle potentially causing a deadly accident. I paid several thousand dollars out of pocket to fix this issue despite GM acknowledging there is an issue with these vehicles.

- New Port Richey, FL, USA

This model corvette can suddenly drop an engine valve (exhaust or intake) and unexpectedly develop a hole in the block accompanied with oil spilled on the roadway, smoke billowing with risk for vehicles behind and in front, and the risk for total loss of power steering, braking and control of the vehicle. The outcome if this happened on a freeway with cars traveling at a high rate of speed is potentially fatal. All of this is due to machining errors and supplier defects for the associated parts (valves, guides, etc.) on all 2006-2013 corvette C6 Z06's made by GM.

- Bolingbrook, IL, USA