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Posted

I have a 2020 SLE 5.3 with roughly 75k kms on it. I've been hearing a lot about imminent lifter failure and am wondering if this is just specific to a batch of trucks or if it will likely happen to me.  I have read a few posts on here but was curious if there's anything listing how many members have had a failure and at what milage it has happened. Any info you can shed on this will be appreciated.

Posted

Lifter failures on these trucks have been around since 2007 when AFM was put into the half tons. The chances of your truck having a failure is pretty slim given the amount of trucks out on the road. There was a small run of trucks that got bad parts a few years ago but if you're truck was part of it you would have been informed of it. Or you can contact a local dealership to see if your VIN has anything come up for a recall or bulletin.

 

 

  • Like 1
Posted (edited)

It has made it 75k miles. Seems like most fail within the first 10k if they're going to.

Edited by 20Denali22
Posted (edited)

What concerns me is there have been several trucks in my town that have had failures at higher mileage with some being right around the 100k km mark which in Canada is the end of the powertrain warranty. 

Edited by NorthernX31
Posted

I've replaced lifters and cams on these with miles as low as 50k and as high as 160k. A few months back I had 2 6.2's in the shop at the same time for lifters and cam, one had ~75,000 miles and the other was pushing 120k. The funny thing is that on both of these neither had a failure on an AFM cylinder. I had a 5.7 Ram in the other day with 48,000 miles that need lifters and cam.

  • Like 1
Posted (edited)
On 4/16/2023 at 10:09 AM, l1tech said:

I've replaced lifters and cams on these with miles as low as 50k and as high as 160k. A few months back I had 2 6.2's in the shop at the same time for lifters and cam, one had ~75,000 miles and the other was pushing 120k. The funny thing is that on both of these neither had a failure on an AFM cylinder. I had a 5.7 Ram in the other day with 48,000 miles that need lifters and cam.

Not trying to argue, but trying to understand the validity of this statement since all of the 6.2 from 2019 up will have DFM, not AFM, and every cylinder will be controlled by DFM.

 

Were the two 6.2's the earlier body style?

Edited by Gangly
Posted

Both 6.2's were pre 2019 so my bad there. I have a close friend that used to work for me that is a Gm tech and he tells me that the DFM motors are experiencing the same lifter failures. AFM and DFM are realistically the same thing with the only real difference being that DFM has the ability to cancel any cylinder and AFM can only cancel 4 cylinders. Other than that you still get the same failures.

  • Like 1
  • 1 month later...
Posted

My 19 AT4 just had lifter failure at 35k miles. I know this is an old thread, but just goes to show, at 4 years old, it’s only a matter of luck i guess! Fixed Bank 2 only to have others come apart on the test drive after. Gm engineer told the tech to replace the whole motor. They also mentioned inadequate oiling in these motors.

No wonder you don’t see any on the lots currently…

Posted

I just joined this dubious club. 2020 6.2 L87 engine with 68,000 miles. Found a good shop and they'll be replacing lifters and pushrods in both banks, along with a new cam. Going to replace the water pump and timing chain while I'm at it, since the existing parts are already being removed. He'll also be disabling DFM for me.

Posted
15 hours ago, alrockaz said:

I just joined this dubious club. 2020 6.2 L87 engine with 68,000 miles. Found a good shop and they'll be replacing lifters and pushrods in both banks, along with a new cam. Going to replace the water pump and timing chain while I'm at it, since the existing parts are already being removed. He'll also be disabling DFM for me.

If you don't mind me asking, how much is that going to cost you?

Posted
On 6/5/2023 at 6:10 AM, BossTaco2020 said:

If you don't mind me asking, how much is that going to cost you?

$2400 for the cam, lifters and repair from that point. Add'l for the parts cost of the timing chain and water pump. Should not be any additional labor as those parts are already removed. He's not a fan of the GM water pump or timing set, so we're going with Melling. I suspect he's cheaper by several 100 than other shops, but more importantly I trust the guy. He rebuilt the transmission in my Hummer H3 as well as a few other transmissions for friends. 

  • Like 1
  • 2 weeks later...
Posted

Shop just got it torn down yesterday. One lifter in cylinder #7 was broken, but the other lifter in the same cylinder had a failed roller that didn't roll smoothly and had flat spots, so obviously the cam is now bad. I was replacing it anyway. Additionally, there's one bent rod so there's going to be one valve that needs replacing.

 

The book time for the project for older (2017) engines was about 21 hours; this one, the book time is 32 hours. He quoted me too low, is willing to stick to the quote, but I'll work it out with him.

 

Since he was delayed a bit, I asked him to order parts from Texas Speed for a full DFM delete. Not sure if we're going to go with LS lifters, Morel or Comp Cams, but I asked him to work it out with Texas Speed as to which are the best bet for me.

 

We looked at the valves in the heads to check out the carbon buildup that comes with these direct injection engines. Here's one valve, and this was middle of the road. Some were significantly worse, some were a bit better. He's going to disassemble the heads and clean it all up.

IMG_2807.JPG

Posted
On 6/1/2023 at 8:13 PM, Bradley E said:

My 19 AT4 just had lifter failure at 35k miles. I know this is an old thread, but just goes to show, at 4 years old, it’s only a matter of luck i guess! Fixed Bank 2 only to have others come apart on the test drive after. Gm engineer told the tech to replace the whole motor. They also mentioned inadequate oiling in these motors.

No wonder you don’t see any on the lots currently…

 

Three reasons for a failure. 1.) Abuse. 2.) Flaw. 3.) Lubrication issue. 

 

Is anyone going to admit to abusing their truck? Over rev. Not changing oil. Improper oil. Overloading. 

 

@CamGTP in his post on April 3 mentioned the flaw. It happens to all makes and models. As @l1tech mentioned in his post on the 16th, this happens to non-AFM lifters as well. Heat treat is usually the culprit. Sometimes machining errors. Usually by batch. When it is the AFM lifter is can be traced to the VLOM sometimes. In high milers the lifter bore wear. Which takes it to reason #3. Lubrication. 

 

When parts touch they fail. Two things keep parts from touching. Viscosity and wear additives. Those additives are consumable and as the industry moves toward its mpg goals and oil for life goal these additives are being relied upon to do the work viscosity should be doing more and more. Sometimes when one walks to close to the edge...they fall off. When GM Engineers say "inadequate oiling' I don't think they are referring to the volume being supplied. Lifter bores don't wear out in 60K-120K if the oil is doing its job. Neither do adequately hard lifters/axles and cams. Not even in a million miles. 

 

Hands in the air, how many Ecotec3 V6's suffer this failure? It does happen. Like finding a Unicorn often. Before someone says, "But there are way more V8's"....lets normalize the statistic by saying how many per thousand units. They use the same parts from the same suppliers. Even the same oil pump. So, what's the difference? Ya all know the answer to that 🤫

 

Let's say 0W20 is actually effective. It can only be so if it STAYS a W20. One of GDI's biggest flaws is fuel diluted oil. So much so that 2.5% is considered 'normal' by everyone but a REAL Tribologist. Okay, and me :crackup:And what happens to viscosity when you dump a solvent (gasoline) in your oil? That said, not the only culprit. VII polymers are not all created equal. And pretty all of them will pass a DEXOS license test battery. Viscosity loss test have a pretty large window and many lube test services do as well before they send up the red flares. This means OCI is critical if you insist on walking the edge of the cliff. 

 

If you insist on using 0W20 then choose one at the upper end of the W20 viscosity spec and one with a 'stay in grade' VII package and one with enough antiwear to cover the silly long OCI's you believe are 'fine' and are not. Or be proactive and shorten the OCI. Don't use a UOA lab that serves up "tasty results' like Micky D. 

 

OR do what you've always done and get the results you've always got. 

 

 

 

 

 

 

 

 

 

 

  • Like 3
Posted

When we built a better mouse trap we got copied. When we used the better mouse trap to do better work we got costumers. That seems to be lost on GM. Changing oil every weekend isn’t possible for everyone. Imagine the wait times if everyone did that. I’ll just buy the better mouse trap. 

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