As long as GM themselves don’t confirm what the root cause is, all we will be doing is speculating.

What comes to your theory, I'm pretty sure people who take extremely good care of their engines (change oil at proper intervals, use high quality oil/filter and never let the engine go low on oil) have had lifter failures. What percentage? Again, nobody knows and nobody will know until GM recognizes there is a problem. Which is never.

Anyway... Guess it's cool to speculate.

 

I maintain my trucks extremely well.

3k oil changes and I still had a lifter fail.

When we pulled the motor at 115k miles and disassembled it, it was like new inside. Truck didn't have a catch can for 100k miles but the intake tract was clean, same with intake valves.

 

Was the lifter failure on your 2015?

 

Sorry to hear that. I just thought I'd float the idea out there because I know plenty of people that just turn the key and go, and then say the car/truck is crap when it breaks. It sounds like you did all you could do and still had a failure. I guess I'm not getting a 5.3L then

 

There are millions of 5.3's out there that don't have a lifter issue. Yes there are some that do, but that is who you hear from. Every engine group and manufacturer has issues. My '17 5.3 runs quiet, flawlessly, and has not a single drip, weep, or oil consumption in 8 years. I do the severe duty schedule for maintenance and got a tune which makes it GO and disables the AFM. Your first statement said a lot. . . . "The internet seems convinced".

 

got 22 mpg in our brand new 5.3 tahoe yesterday, long interstate trip. so far i love DFM!!

 

My truck is 2022 refresh model manufactured in the summer of 22. It's a Denali with a 5.3. There was a chip shortage at that time so, the engine dose not the DFM chips. For my best gas milage, see below.

 

There's a GM guy on Tik Tok I follow that has a Tahoe with close to 250k on it and he's never done anything with the valvetrain. So I know there are success stories out there. There's so much doom and gloom regarding this subject, that I'm not leaping at the idea of dropping 50k on a truck, just to have this happen. So do I have cautious optimism or run? I guess I was hoping that people would say if you maintain it properly, you won't have an issue.

 

I guess I was hoping that people would say if you maintain it properly, you won't have an issue.

Unfortunately that's not how it works. My well maintained (by the PO and myself) 2016 just turned 230K miles and has had no issues. If it ever will, I will invest a few grand on an AFM delete kit and keep on trucking. There is no new truck in my foreseeable future.

 

The main plan is a daily, that will haul things on occasion, so the Turbomax is a consideration. But I just wanted to see what people here would say.

 

AFM/DFM Failure Route Cause?

Dirty, old oil is AFMs worst enemy. The WRONG oil is an enemy to AFM. Lots of people put the wrong oil in their engine and then wonder why VVT and AFM isn't working right.

Next up are the solenoids that get out of time which causes the oil to collapse the lifters at the wrong time, damaging them.

There are only a handful of lifter trays that keep the lifters from turning and wiping out the camshafts.

It is SOP to replace the lifter trays and VLOM anytime an AFM repair is made. Many ignore this directive to their own wallet's demise.

Use the right oil and change it every 5K miles and the system will last a very long time.

 

Could you describe wrong oil? I just put oreillys 5w-30 synthetic in and am kind of kicking myself. Will definitely put Mobil one or something better in next time

 

I wish i had $1000 for every time someone started a thread like this, thinking they're postulating something new, when they're not.....
And ill say it again.....The reason you see so much of it on the internet is because you only see the bad shit. In actuality, the failure numbers are really low. I'm right behind @tsuintx with 211K on my 2015, and it hasn't missed a beat. Been flawless since I bought it.

 

This is why I posted the thread in the first place. To determine once in for all, are the owners to blame, the manufacturer, or some combination of both. I'm glad to hear you guys are standing behind your 5.3L. I didn't mean to strike a little nerve. The only things I've seen on the internet are "Gm lifters are defective" and "Gm makes garbage engines" that's basically all I've seen on the internet. I'm not "postulating", I'm floating an idea that I haven't seen yet on the internet. Change your tampon, crack open a wine cooler, and relax🤣

 

It'll be both. The afm lifters are more prone to failure (siightly) than non-afm lifters, and poor maintenance will increase the likelyhood of failure. But the first is only slightly more, maintenance will have a much larger affect.

 

It seems to be that way. One guy here has two trucks maintained the same way and one had valvetrain failure and the other didn't. But it also sounds like proper maintenance significantly reduces the chance of failure. I know, not a revelation, but this whole thing seems blown out of proportion by what being said on this thread.

 

WTH?
Nobody is going to post "I haven't been maintaining my vehicle well enough, and now the engine failed." Of course it's gm's fault, every time.

 

WTH?
Nobody is going to post "I haven't been maintaining my vehicle well enough, and now the engine failed." Of course it's gm's fault, every time.

So sarcasm aside you agree, it's blown out of proportion. And people don't take responsibility for neglecting their vehicle. They would rather blame the manufacturer. I understand no one will admit they neglect their vehicle. What I'm trying to figure out is why it's happening? In denial or not, is it lack of maintenance that is causing the failure? Jesus tap dancing Christ

 

IIRC didn't the earlier Gen DOD systems had an oil pickup tube with a screen that could get clogged with sludge, leading to failure...?

 

I appreciate all the feedback (even you Roorancher 🤣) and understand that it's a combination of both design and lack of maintenance that causes the failures. Some of you have pretty good runs going with your 5.3L's and that says something.I feel better informed now. Bowtie til I die, Thank you 🫡

 

The 5.3s are nice. They have some lifter issues, but so did the 5.7 hemi.

The 5.0 coyote has some issues with the cam phasers.

Seems like they all have some issues.

The TurboMax seems to get good reviews for reliability as long as it's not towing too much.

 

I had a F150 (bought at auction at 61k miles) with 5.0 coyote. Had to replace phasers and timing chain under 70k miles. Truck was eating 1/2 quart of oil every 500 miles! Traded in while I could and now 2 months into a 2019 GMC sierra elevation with 5.3 at 45k miles. So far I love it!

 

While maintaining these engines is key, and it does get blown out of proportion online, the entire AFM/DFM system is hot garbage.

You couldn’t pay me to own a vehicle with it. And if I did, I would be deleting it asap.

Father had 2 of 3 trucks fail. And I know to a T (because I did it) that the oil was changed and always ran good oil. His 2009 failed twice, first time it got cam and lifters and second time it got a whole new long block because the failure wiped the mains.

Then his 2018 failed just before the warranty expired, and that truck we had a range module installed since practically day one.

The parts are just junk, and as far as I’m concerned, there is nothing you can do to prevent a failure. Sure you can change the oil religiously and disable the system, but that doesn’t stop junk parts from failing.

So the root cause is simply poor design and poor part quality.

 

the issue gets a lot of attention because, while it occurs infrequently, the repairs are quite expensive. i just lost a 6L90 converter after 120k easy miles, while my brothers AFM tahoe went 200k before he disabled it electronically and it is still going strong.

At the end of the day, you pay your money and you take your chances. If there was an AFM-free vehicle on the lot next to an AFM-enabled vehicle on the lot that was otherwise identical and cost the same, i would buy the one without AFM. That is not the world we live in, and all things considered my feeling is that the current GM offerings have enough other strengths to offset my concerns about AFM/DFM.

Plus my wife said we were getting a damned Tahoe whether I liked it or not 🤣

 

I have a 2011 Chevy, Silverado 1500 like torque converter blew apart, took out. My transmission took out my training line, my cooler. Last second I didn't even know what was going on, I was driving it perfectly and all of a sudden, this started making some funny weird things. I was able to limp at home. And then the dealership told me that they wante10,000 4 to replace the transmission. I went to l and l transmission in Batavia. It cost me $6800 to go through everything and replace everything. And that was pretty reasonable, but still expensive GM better step up and fix these problems, which they won't

 

You're fine. 5w30 synthetic is perfectly good, regardless of brand name. Just change it every 5,000 or so and use a quality filter.

(Edit: I should have mentioned; as long as the oil is Dexos approved.)

 

Could you describe wrong oil? I just put oreillys 5w-30 synthetic in and am kind of kicking myself. Will definitely put Mobil one or something better in next time

Could you describe wrong oil? I just put oreillys 5w-30 synthetic in and am kind of kicking myself. Will definitely put Mobil one or something better in next time

If your vehicle calls for oil meeting the Dexos1 Gen2 standard, then whatever oil you choose ought to meet that standard and they'll have the logo somewhere on the bottle. Oil is now asked to do work inside an engine, not just lubricate and cool. We often see VVT problems because people are running oil that doesn't meet the minimum GM specs for their engine.

I quit regular Mobile One years ago, too thin and way too much dissolved metals in my oil.

 

Which oil do you use?

 

I lost my 5.3 after 10 years of driving casually, changing the oil every 5k with AMSOil (15k oil) and Wix filters at 56k miles. I am so lucky to be in the top 10 percent....... I really despise the AFM/DOD. I had better gas mileage out of an 82 Surburban Trailer Special with a 383 stump puller at 24 mpg.

 

If you are buying a 2025 I'm not sure a Diablo is ready yet for the newer model trucks? The Diablo plugs into the OBDII Port which disables the cylinder cut-out on the engine. Plug and Play. I have a friend I recommended the Diablo to, he says his mileage didn't change?

I purchased a 2022 Chevy Silverado. Because of the parts shortage GM didn't have the chip needed for their cylinder cutout feature. I actually got a $60.00 reduction on the sticker. When I told the sales guy if any new 1/2 ton trucks with the 5.3 had the AFM? That was a deal killer for me. I told him exactly what I was looking for, and he brought a truck out with everything I wanted. It was perfect.

It seems all Manufacturers have their issues. GM has issues with some of their fuel pump modules. Others have transmission issues? AFM and DFM problems. The 6.2's are developing a bad reputation more so than the 5.3's. Allison transmissions seen to have more problems than the GM Ford hybrid transmissions. It's the luck of the draw. Do your homework and make an educated purchase after you understand what flaws each manufacturer is dealing with. That said, I absolutely love my 2022 LTZ!

Good Luck!

 

Your 2022 LTZ has AFM - yes?

You said AFM was a deal breaker but then you purchased a 22 with AFM???

 

When I got my 6L80 rebuilt after the TCC took a dump, the transmission shop had several Silverado's there all for the same rebuild. Not a single F-150 in there. Lots of Nissan Rogue's too for a CVT swap. They do great business with 6L80's. The pain is real. Likewise for the V8 lifters, they have a higher rate of failure. The consensus is that disabling AFM and using clean oil helps some, but is not a sure thing. I am at 134K miles, no failure yet, but know it is a risk. Definitely will do a hardware delete if it does fail, and cry about the cost.

 

AFM lifter failure is THE reason why these engines fail. Without going into whether it’s a poor design or planned obsolescence or both, I will give my opinion on root cause.

The AFM lifters fail because they are a small lifter INSIDE the body of a regular lifter, essentially. The smaller spring fails overtime because, well, it’s too small. Or the small body of the lifter gets stuck somewhere in the main lifter body and hyper extends when it finally releases.

I’ve deleted an ‘08 and an ‘18. Both got stuck and hyper extended upon release. The ‘08 broke the valve spring and the ‘18 lifter failed internally bent the pushrod then collapsed inside the lifter.

I work in or next to the street for a municipality. I hear GM’s with lifters ticking ALL THE TIME. It’s a bigger problem than what’s being reported online.

 

This comes from a GM sales rep:
"Spring failure due to poor quality AND this has been remedied - supposedly"

 

I have also searched the internet on this issue. There are people that have religiously changed their oil with quality synthetic oil every 5000 miles and have still had a lifter failure at low mileage. That tells me it's someting more than dirty oil. I have a 2021 Trail Boss bought brand new that is a Covid truck and did not come with the AFM chip, " thank God." But my 2011 Suburban 5.3 liter 6 speed came with AFM. I made note of watching how many times it switches from 8 to 4 cylinders as i drove it. It was unbelieveable how may times it went back and forth betwen 8 and 4 cylinders.. That is to many moving parts for me at to many times.. For a piece of mind I put an AFM disabler on last week at 170,000 miles. I must have got lucky making it this far without the disabler.I feel the diasbler is a personal thing, i"m not avocating it or against it. This video link convinced me to put the disabler on. It sounds to me like it's more of a mechanical / timing event that causes the lifter failure.

 

Bad Idea design with poor quality parts and you have a GM Disaster.

 

Prospective 5.3L buyer here as well.

Any updates?

 

The root cause is lifter failure.
But why they fail has not been determined.
It can be as simple as a machine tool in the lifter machining process getting dull.
Or a batch of steel that is still acceptable but on the lower side of specs.
Maintenance could be the cause but some well maintained have also failed.
The list of things it can be is many and differ between mechanics.
The engineers at GM need to find the cause and fix it, if they can.
Personally, I will not buy one that has this system installed.
If I want to gamble, I will go to the Casino.
This system came out in 2008 and is still not bullet proof.
If I was the head of GM I would scrap it, along with the start/stop thing.
Now is the time to work with the EPA and refine these specs so they are possible through the Laws of Physics.
The consumer need not be the test track for car makers.

 

GM knows what the causes are.

#1 - Poor quality components = springs were breaking

#2 - Dumb-arse idea of shutting off cylinders in a V8 truck no less

Never had an issue with my 2012, 2016, 2018 Tundra where all 8 cylinders run without the need for techno-arse