2021 Suburban LM2 reliability sob story

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Jim Meehan

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Bought new Jan 2021. I love this vehicle in concept -- the combination of seating, cargo capacity, towing and fuel economy are all great and not to be found in any other vehicle really. But it's been a reliability nightmare, compounded by poor service experiences at multiple Chevy dealerships.

~1000 miles: Coolant leak due to mis-installed hose at the factory. Slow enough not to notice any drips, but eventually the radiator fan was running on high all the time, and I saw the coolant overflow was totally empty. Service told me both of these were totally normal the first two times I took it in. Finally took it to another dealer who found the problem. How can there not be a low coolant warning before something gets hot enough to make the fan run all the time?

~10000 miles: Failed EGT sensor. It took them weeks to get a replacement due to supply chain issues, during which we couldn't really drive it because there is a speed limit countdown for emissions-related problems, just like when the DEF is empty. And then they replaced the wrong f'ing EGT sensor! So CEL was back on within 100 miles. Fortunately the part was quicker to get the 2nd time. Dealer had no loaners or rentals available during all of this, though GM did reimburse me for a rental I got from Avis.

~40000 miles: Failed turbo coolant pump. This caused the vehicle to go into a boost-limited limp mode on a road trip to Disneyland, top speed 40 mph going up any kind of grade. Thank god we weren't towing. We made it back home and the service experience was okay this time.

~85000 miles: Exhaust leak up front somewhere, strong exhaust smell in the cab whenever the engine is running and vehicle is not moving. Yet another dealer has had it 3 1/2 weeks now. Only one diesel tech, they are supposedly 90% into a deep disassembly to determine where the leak is. Warned me there could be a wait for parts depending on what they find. No idea yet if it will be covered under the powertrain warranty. This dealer told me "we don't do loaners or rentals." Period.

Feeling frustrated. I'm tempted to get rid of it whenever we get it back, but I don't really know what I'd replace it with that wouldn't be a big compromise in terms of how we use it. The loan on something new would also come with a much higher interest rate than the 2.5% on the current one.
 

DuraYuk

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Sorry to hear man. Your problems wouldn't be a big deal if you had quick parts turn around and a competent service department.
 
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Jim Meehan

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Sorry, but you’re not going to convince me that four powertrain issues within the warranty period would be just fine if the service was better.

Besides, it *wasn’t* better. Poor service at three dealerships across two states seems like more than a coincidence. You might say that GM doesn’t control how individual dealers operate, but I’ve read they’re actually pretty heavy handed about how dealers run their business. Just look how much they made dealers spend remodeling their buildings for a consistent look nationwide. You’d think GM could mandate consistently great service as well because it’s equally as important for their brand reputation as building reliable vehicles.
 

DuraYuk

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Sorry, but you’re not going to convince me that four powertrain issues within the warranty period would be just fine if the service was better.

Besides, it *wasn’t* better. Poor service at three dealerships across two states seems like more than a coincidence. You might say that GM doesn’t control how individual dealers operate, but I’ve read they’re actually pretty heavy handed about how dealers run their business. Just look how much they made dealers spend remodeling their buildings for a consistent look nationwide. You’d think GM could mandate consistently great service as well because it’s equally as important for their brand reputation as building reliable vehicles.
I'm not convincing you. If you hate it sell it.

A coolant hose ? A sensor ? A coolant pump? An exhaust leak they can't fix?

Dude that's child's play. That is all stuff that takes no time to fix.

I've worked warranty for gm. The shit I've seen makes me laugh at what your describing.

Break downs suck no doubt. I wish a machine existed that was man made with no downtime. Even the king toyota has issues.

With that said good techs have always been in short supply. The pandemic and lack of pay has made it worse. So while you had multiple dealerships this problem is national if not global across all brands.

If unhappy move on. Then come post how that new ownership experience is so we can decide if it's worth it. Maybe we will switch too.

Good luck man.
 

StephenPT

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Bought new Jan 2021. I love this vehicle in concept -- the combination of seating, cargo capacity, towing and fuel economy are all great and not to be found in any other vehicle really. But it's been a reliability nightmare, compounded by poor service experiences at multiple Chevy dealerships.

~1000 miles: Coolant leak due to mis-installed hose at the factory. Slow enough not to notice any drips, but eventually the radiator fan was running on high all the time, and I saw the coolant overflow was totally empty. Service told me both of these were totally normal the first two times I took it in. Finally took it to another dealer who found the problem. How can there not be a low coolant warning before something gets hot enough to make the fan run all the time?

~10000 miles: Failed EGT sensor. It took them weeks to get a replacement due to supply chain issues, during which we couldn't really drive it because there is a speed limit countdown for emissions-related problems, just like when the DEF is empty. And then they replaced the wrong f'ing EGT sensor! So CEL was back on within 100 miles. Fortunately the part was quicker to get the 2nd time. Dealer had no loaners or rentals available during all of this, though GM did reimburse me for a rental I got from Avis.

~40000 miles: Failed turbo coolant pump. This caused the vehicle to go into a boost-limited limp mode on a road trip to Disneyland, top speed 40 mph going up any kind of grade. Thank god we weren't towing. We made it back home and the service experience was okay this time.

~85000 miles: Exhaust leak up front somewhere, strong exhaust smell in the cab whenever the engine is running and vehicle is not moving. Yet another dealer has had it 3 1/2 weeks now. Only one diesel tech, they are supposedly 90% into a deep disassembly to determine where the leak is. Warned me there could be a wait for parts depending on what they find. No idea yet if it will be covered under the powertrain warranty. This dealer told me "we don't do loaners or rentals." Period.

Feeling frustrated. I'm tempted to get rid of it whenever we get it back, but I don't really know what I'd replace it with that wouldn't be a big compromise in terms of how we use it. The loan on something new would also come with a much higher interest rate than the 2.5% on the current one.
Failed turbo coolant pump (I'm assuming by this you mean the CAC coolant pump) was likely caused by corrosion in the wires. The connector is oriented vertically and there is a TSB out that mentions some of the connectors did not have the seals fully seated and allowed water in on the backside of the pins.

Another forum member had strong smells in the cabin from an exhaust leak at the turbo. I believe the fix was a new turbo. Search for @steiny93 thread about it.

I agree that these rigs should have better reliability. I wouldn't be here if Honda/Toyota had a comparable offering - though more recently their products seem to have more issues than their reputation would suggest. There is nothing that comes close in the interior volume and offers as efficient of a powertrain as what GM has on the market.
 

steiny93

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Sorry, but you’re not going to convince me that four powertrain issues within the warranty period would be just fine if the service was better.

Besides, it *wasn’t* better. Poor service at three dealerships across two states seems like more than a coincidence. You might say that GM doesn’t control how individual dealers operate, but I’ve read they’re actually pretty heavy handed about how dealers run their business. Just look how much they made dealers spend remodeling their buildings for a consistent look nationwide. You’d think GM could mandate consistently great service as well because it’s equally as important for their brand reputation as building reliable vehicles.
totally agree, powertrain issues are an indicator of quality, gm is on that struggle bus and the service experience isn't doing them any favors

To be fair to @DuraYuk per https://www.usatoday.com/story/mone...ts-most-reliable-cars-trucks-suvs/6385214001/ those of us who have the 2021's should expect issues. The 1500's from Chevy/GM being the #4 most unreliable vehicles and all.
 
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Jim Meehan

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Failed turbo coolant pump (I'm assuming by this you mean the CAC coolant pump) was likely caused by corrosion in the wires. The connector is oriented vertically and there is a TSB out that mentions some of the connectors did not have the seals fully seated and allowed water in on the backside of the pins.

Another forum member had strong smells in the cabin from an exhaust leak at the turbo. I believe the fix was a new turbo. Search for @steiny93 thread about it.

I agree that these rigs should have better reliability. I wouldn't be here if Honda/Toyota had a comparable offering - though more recently their products seem to have more issues than their reputation would suggest. There is nothing that comes close in the interior volume and offers as efficient of a powertrain as what GM has on the market.

Just heard from service this morning. The current issue is a cracked exhaust manifold. Covered under powertrain warranty thankfully, but it's going to be at least a month and maybe two before they can get a new manifold. Magically, they do now have a Silverado available as a loaner.
 

UsualSuspect

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Issues are tolerable, what makes it intolerable is the wait for parts. Hopefully now that folks are not buying as much, parts become readily available, or at least 1 or 2 days out. All of the manufacturers have quality and parts issues. You basically have 2 choices, wait it out, or trade it and get something else. The problem with something else, you know what you have now, but don't know if what you will get will be more reliable, or be worse than what you have already.
IMHO I would wait it out, I have vehicles from Ford, RAM, Toyota, Honda, and GM. None of them are immune from breakdowns and parts issues, GM is not alone. Good luck with your decision, hopefully the parts come in faster than expected.
 

dbphillips

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Just heard from service this morning. The current issue is a cracked exhaust manifold. Covered under powertrain warranty thankfully, but it's going to be at least a month and maybe two before they can get a new manifold. Magically, they do now have a Silverado available as a loaner.
Do you know if there is a TSB on this? My dealer doesn't seem very interested in finding the source of the diesel smell in the cabin of our Tahoe RST (what idiot designed the exhaust to exit underneath the truck?!).
 

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