New Service Bulletin Addresses Valve Spring Issues In GM V8 Engines118
General Motors has issued a new service bulletin to address the valve spring issues some of its newer V8 engines are experiencing.
The service bulletin indicates that vehicles equipped with certain GM V8 engines may produce a service engine light along with a misfire and strange engine noise. The issues can be linked back to faulty valve springs, with the bulletin instructing the service department to check for a broken valve spring and, if necessary, perform a cylinder leakage test on the cylinder with the broken spring. The bulletin also says that “if no cylinder leakage is observed it will be necessary to replace all valve springs on both banks if the vehicle is built between June 1, 2020 to September 15, 2020.”
The bulletin also indicates that the above fix only applies to the following 6.2L GM V8 engines: L87, LT1, LT2 and LT4. For all other current GM V8 engine RPOs (L82, L84 and L8T), the service department is instructed to “just replace the affected valve spring,” and that if they determine there is a cylinder leakage, it “will be necessary to inspect further to determine the extent of the engine damage to determine correct repair required.” GM is also requesting that the service department send back valve springs from affected engines for further inspection.
This service bulletin can affect a very large range of current GM vehicles. The LT1 and LT4 V8s are found in the Chevrolet Camaro, while the LT2 V8 powers the Chevrolet Corvette. The L82 and L87 V8s are found in the latest GM full-size truck and SUV models, while the L8T is offered in the Chevrolet Silverado HD and GMC Sierra HD trucks, along with the Chevrolet Express van.
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My 2020 Corvette C8 was towed off yesterday. Misfire, no oil pressure, wouldn’t stay running. The car has 115 miles on it. Very sad! It sounds like the valve spring issue. The dealer where it was towed hasn’t even looked at it yet.
After 50+ years of GM loyalty. . . I have decided. I am done. After dozens of cars, and trucks. I have given up on the weak engineering, and the short comings on quality power plants. As licensed mechanic. . .I do have a clue. I have 2 left in the driveway, and they will be gone soon. Something needs to change, and it needs to happen fast. GM is losing Good Solid Hard Working American Market share. Somebody has been asleep at the wheel for too long. Quality matters, the American consumers are educated. GM seems to be losing sight of Priorities. The customers that have “Kept” you in Business. . . . Certainly should be your priority. If the Parts are Weak, Substandard, are Marginal. . . Step Up. Make it right. I have decided. . . It is time to Sell out, and Shop around. GM has already Sold Out. It was a Good relationship while it lasted, but somebody got confused, and distracted. Times are changing. Keep Up.
Partner, I feel the same way. I have owned 23 gm vehicles and have had a problem with one and I complained and gm couldn’t care less. IMO.
I.have had it with GM. I just sold a Buick.Grand National, had a new CTS V, ordered a corvette, new 99 Riviera (which was rock solid one of the best cars in 35 years). I now have Sierra Denali with the L86.and the POS 8.speed transmission which I hate. My 392 SRT Chrysler 5 speed was better. Quit going cheap.ass on parts GM. My next vehicle will most likely be a TREX hellcat ram or SC V8 raptor. Probably saying see you to GM!
So this finally explains it… Just got a new 2020 silverado trail boss w 6.2 this month & had it 3 days & 145 miles & it suddenly started acting up & shut off in traffic & wouldn’t restart. Aftr a long process of getting it towed & 2 dealer (thanks roadside assistance) they looked @ it w help from mechanics @ GM & determined it had a broken valve spring & that led 2 catastrophic engine failure. So now they r putting in a new engine & components. I’ve been w/out it for 11 days & not goin 2 get it back til sometime next wk. This is so frustrating. What was my dream truck is now a nightmare. Couldn’t find any1 else sharing this kind of issue til this came out. So disappointing. Mind u I love chevy & bleed bowtie & have only had silverados for many, many yrs & only owned chevys & im not going 2 defect but this is super upsetting. & oh yeah, i called chevy customer service 2 complain & was told they would get back 2 me in 24 hrs & guess when they did… A week later. Nice, right?
I gave up on gm after 6 vehicles all were junk. Nothing but the blue oval now and no problems since 91. Cut your losses and get out if you can
Brand new 2020 GMC SIERRA AT4 6 2L….broken valve in first week, under 250 miles. Unbelievable!!
No valve issues or any other on my terrific 2018 F-150 with 5.0 twin injected OHC. I’m already up to 75K on it.
Same here! Less than 150 miles on mine when the first break down happened. Broken valve spring #2 cylinder. Towed to dealership repaired had delivered to my work. On the way home broke down again! With less than 230 miles. Towed again now the #4 cylinder valve springs. Told dealership to take truck back and washed my hands of that nightmare. Got another AT4. No problems yet. Fingers crossed!!
Mine made it a whopping 316 miles before being towed in… Broken valve spring. They only replaced the one though… Wondering when the next goes bad. This is crazy, I’m still waiting to hear what they are going to do. I’ve heard some have received a coverage component letter, basically extending the powertrain warranty to 100k miles. Dealer anticipates a response in the next few days.
Same thing happened to me 2020 trail boss 6.2 with 300 miles. They replaced 1 valve spring! I guess I will get towed a few more times possibly?
I would like to read the service bulletin to confirm the model years and/or VIN ranges affected by this.
Engines built between 6/1/20 and 9/15/20.
Its not hard – google gm service bulletin &/or valve spring issues w V8’s, etc. It lists which engines r effected & the date range is June 1st – Sept 15th 2020. My engine is the L87.
So do we think they are gonna use different valve springs after sept 15th? Or just keep using the same?
It is impossible to test every part. Suppliers are mostly self certified…
There’s no surprise here at all. GM is basically an assembler of Chinese components. Only when you are vertically integrated can you maintain full control on quality.
No surprise at all GM like many companies are going with the cheapest priced suppliers now.
2020 trailboss 6.2. Bought 2 days ago. In shop with valve spring failure. 603 miles on it. Great quality Gm. Should have stayed with my Tundra.
This valve spring issue is it all engines mentioned that were built in that time frame or is it random I have a sierra with an L84. built in August it has 2500 miles on it now just asking.
I was told by A GM employee, That the problem was “Fixed the Problem” BY Computer Up Date!? That would mean it is a signal sent to the Camshaft sensor to Advance OR Retard the cam timing. ANY Change from designed ramp up or down will have a negative effect on Performance. Taking MORE Time to make the desired Change.
That sounds like the dumbest thing that I’ve ever heard. I just picked up my 2020 Corvette after being gone 19 days. They changed all 16 valve springs. Had 115 miles on mine.
Nancy, Perhaps you are not aware of how Your VVT works? On older models (LS) Cam timming (VVT) was done using oil pressure to advance the cam. The NEW LT engine uses electric impulses to advance and retard cam timing. If you slow the advance or the retard it puts less initial pressure on the Spring. Boltzmans Calculation for this is: S=k.log W.
Harry, What is your point. I paid a lot of money for my car and waited 13 months for it. GM should be ashamed of themselves. This is my 21st Corvette. It seems like you’re making excuses for GM. I do not want to be stuck on the interstate when my car breaks down and get killed. With all of the traffic in Florida I want to feel safe in my car.
Nancy, I AM NOT making excuses for GM. I am as abhored as you at this unfortunate happening with ALL V8 GM engines assembled during the times given. It IS a bad batch of valve springs, and IF Mine had been built during the specified times, I would INSIST the dealer put in NEW SPRINGS Before I drove it! I first wrote that GM slipped op on QC. (Quality Control) I was sort of booed for that post. The cause was explained to me by a GM engineer. I am sorry for your depression. GM Screwed Up! I ordered a 2021, and Hope the flaws are worked out. For you I am sorry. Sincerely.
sorry but cam timing and a computer will not have any effect if you brake a valve. I worked in engineering for 34 years and know for a fact that GM has gone to cheapest supplier on everything now just like most of the other car companies. We use to test everything before it went into a car then it was one out of 5 and when i finally retired it was just let the suppliers do all of the testing on their parts. Give me a break if i am the supplier of a part making millions my part is never going to be bad. NEVER
While surface issues or Loads etc can be 100% detected …. it is IMPOSSIBLE to detect “sub surface” issues on total production batch of Springs. Sub surface issues can be ‘inclusions’ (typically .004 to .007″ toward ID) (not much of a problem in Steel rod since 2000) or due to high heat/quench spring processing. The heat treatment issue is a lot more more prevalent than inclusion.
When parts are fatigue tested at very high G’man stresses to 10 Million cycles, it doesn’t mean that all 20,000 springs or so from that batch are perfect. No. In general, parts in the engine will rarely see the G’man stresses that they go thru testing.
I just picked up a new 2021 Camaro RS with the LT1 engine. Put 21 miles on it and it started to miss and run rough. At dealer now think broken valve spring. Lovely 21 miles what a joke
Yup confirmed broken spring
Unfortunately there are 15 more to worry about. My plan was to buy the last MY Camaro slated to be 2023. I’ve been reading all these texts and I’m really thinking about my plan
They replace all 16
How long did they have your car?
picked it up on Friday and it started to miss Saturday. Put a total of 21 miles on it total with delivery has 34 miles on it
Damn I picked up my car from the dealership yesterday. Broken spring number 7 cylinder. Looked at paperwork and they replaced only 8 springs only on the side that the one broke on. What the hell? According to bulletin they were supposed to replace all 16. They better hope another one on other side doesn’t break or they can have the car back. How cheap can you be.
When mine broke at 115 miles they replaced all 16 valve springs. You are correct the bulletin says all 16 must be replaced.
My 2021 Sierra AT4 broke at exactly 115 miles too. Was idling in the driveway for 5 mins and all hell broke loose. Dealership is contemplating full engine replacement as valve dropped, rod bent, etc. Came off the line 10/31/2020
Dante, I would take it back, & inform them they need to replace the other 8 (like they were supposed to do in the first place).
They told me that it is now a engineering decision and they have to do what the engineering department tells them to do. They tell them what happened and miles on vehicle and they decided if all or only some get replaced. The parts come directly from the engineering center checked before installing them. Funny but I worked for the engineering department for 35 years and can see how this would happen. The management was really cheap and getting cheaper and cheaper when I finally retired in 2015. Blame Mary B
That is very unfortunate! I understand…it sounds like a run around to me though. “Engineering” is not driving your vehicle. I’ve heard mine was shipped to Denver from Arlington, on the 3rd. Now I just have to wait for it, to be shipped to the dealer here in WY. I can only hope that it will not be one of the percentage with issues. I really hope your other side is okay!
This can be considered a safety issue and Chevy needs to do a recall on all the engines that have the bad springs and replace all 16 on their dime and the owner gets the use of a courtesy car for the duration of the repair. The consumer needs to hit GM where it hurts. In the wallet!!!!
You are exactly right Lynn! GM “should” do a recall, to replace ALL 16 valve springs! I have to say I’m concerned that the time frame they quoted may be a bit under stated. My 2021 Yukon XL Denali was just built last Saturday. I am hopeful that it won’t have this issue. However, I won’t know until the 2 hour drive home from the dealer. Getting stuck in the middle of nowhere in WY, with possibly no cell service, is not an appealing thought.
And I thought I lived in a rural part of PA. It’s always tough to put your foot to the floor now because you can’t trust the engine not having a problem. I’m dealing with a similar problem with my malibu but it’s the transmission causing me problems. We spend all this money on these vehicles we shouldnt have to worry if they are gonna be breaking down.
I agree. I used to live in rural Berks County PA. The speed limits are much higher out here (70 mph), for the drive home from the dealer. There is also a possibility you may not see another driver, for half an hour or more. There are more animals here than people. LOL
Should have bought a Ford. You could drive it to hell and back in full peace of mind.
R u related to a certain Henry Ford by chance?
Never happen. The small percentage of vehicles that will be affected they will just fix them as they get them. Remember of all the engines that are out in the field maybe 20% will have a problem and some might not have a problem till the warranty is up. No way GM or any car companies would fix them voluntarily.
Seems like a good majority of the people with the 6.2L are having the problem. First and last Gm for me!
Actually only a very small group are having problems. They have done a great job fixing my 2021 RS LT1 love this car it is a blast to drive and I get compliments on it every time I drive it.
Funny how they are acting like this is a 2020 model problem. I have 2014 Sierra 6.2l that has had 2 broken springs in 107k. I thought they would have fixed this issue by now. I was a huge GM fan until this truck. Two broken springs left me standed in the middle of nowhere. A/C condensor has gone out twice, random service trailer brake message and today a coil pack went bad. I’m afraid to drive it anymore. My next truck won’t be a GM product.
Bought new Silverado 1500 RST 5.3 motor on November 9th 2020. Truck broke down on side of highway on 11/22/20 and has a broken valve spring. Service thought initially had damage to piston and potential damage to cylinder wall, which now they state it’s only the spring. I’m very concerned this will lead to further issues. Thoughts??.
I’d be concerned too. Right now, the best thing to do is make sure you keep all the paperwork from the repairs so you have written proof if this turns into other problems and when(if) there is a recall or a lawsuit against GM you will have the proof you need
I think it is BS. This engine has been produced for years i think that GM needs to start looking at the supplier chain and stop buying parts from the cheapest supplier. When i was working in engineering GM and some of the other car manufacturers started to outsource more and more parts to outside companies that would be made by GM. The problem is they always told the buyers to go with the cheapest bid and did no testing on the parts leaving that to the suppliers. If i am that supplier my parts will always pass no question GM did not even check the testing at the plants. Now the testing for most of the parts is all done by the suppliers very little is done in house like when i worked in lab. All you are doing GM is making people buy from another company your product is now garbage. I have always bought GM products and i am 65 now but my next car will not be a GM.
Agree, but what car company doesn’t do what you say GM does?
all of them are doing that now it is a real shame
Because of this issue, I walked from a deal – 2021 SS2 1LE. It’s disconcerting to say the least. Strictly from consumer perspective, who in their right mind will knowingly buy a problem. Technically I can see both sides of the coin – supplier and OEM (Chevrolet). Unfortunately I can’t quantify making the purchase knowing the car’s fate and my peace of mind is left to the judgement of a service tech and dealership to do the right thing and replace all springs versus replace the faulty spring as described in the bulletin. If I had stellar experience before I would mitigate risk by looking for a model built after Sep 2020. However, I’m reminded of prior subpar service with Chevrolet in the past – 2 brand new cars. Poor service. Disappointed as I was excited to close the deal.
Well I do agree to a point but I have always had great luck with my cars up to this time. They did a good job fixing my car and so far I have had no problem with it and it is a blast to drive. I have always wanted a Camaro and I love this car. Looks wonderful and driving it is a lot of fun. I was a little mad when they only replaced the one side but so far so good. Was impressed that they gave me a brand new blazer to drive while mine was in shop really nice vehicle. Not going to be scared wanted it and so far glad I got it
My plan right now is to buy the same car u passed on but I want the 2023 model year. It’s supposed to be the last yr for the ICE Camaro. With every thing I’m reading I’m getting a little worried. Hopefully Chevy gets this issue fixed along with the starter problem by then. I don’t want to buy a challenger but I may have to.
Same issue here. Had the truck (High country) for 2 days. Maybe put 50 miles on it.
As a consumer, what are our options?
Get the vehicle back to the dealership,get everything in writing. Get in touch with a lawyer. I thought that the engines were run at the factory
Just think if you had put out 80k for a new corvette and had this problem.
Nearly 70k in my truck. I feel your pain!
Unfortunately not a lot you can do. Hopefully they fix it correctly when they take it to dealership and you have no more problems. Mine so far has been good. Have 520 miles on it now and is running great lot’s of fun to drive.
My AT4 had a valve spring go at 316 miles, quite frustrating. They fixed it and got my truck back to me quickly. I was able to get the power train warranty extended to 100k miles. Then i found out they only replaced the bad one. I sent the service mgr the technical service bulletin and now it’s back in the shop gettinlng the other 15 valve springs replaced, I’ll be happy to get it back tomorrow.
I complained when they only replaced 8 of my springs and they told me that it is now up to the engineering department to decide whether they replace all or only some.
Pat, where did you find a copy of the TSB?
Have to go to the NHTSB site and check
Not much. Dealership fixed my broken valve spring. Worked with GM customer service and after several weeks of review, they extended powertrain warranty to 100,000 miles. Good luck!