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Question on AFM collapsed lifter failure

Doublebase

By Doublebase
in Engines & Drivetrain

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Doublebase Enthusiast

Doublebase

Posted
Posted

I don't know much about this system, how it operates, the stress that is placed on the lifters during cylinder deactivation. How common is this failure? Been watching some YouTube videos on the repair and it's very labor intensive...heads have to come off, etc. I see that you can buy the entire kit (lifters, gaskets) for around $500.

 

Have a friend that told me...just change your oil, you'll be fine. The number one cause of this failure is neglected maintenance. That true? Or is it an inherited problem with the design of the system? 

 

The system came out in 2007, there must be some improvements made to it since then, no? 

 

I must say that the AFM is allowing me to get some excellent fuel economy out of a full size truck.

 

So is this a common problem, or are there people with 200,000 on these trucks that never had an issue with it?

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Grumpy Bear
Grumpy Bear

Not enough to mount a class action 😉    There is a small percentage of these motors that had actual stress failures due to some manufacturing defect like a heat treat issue. But by and large

WesternMike
WesternMike

115,000 on my 14 with not a single problem, like not one issue at all with this truck. Mobi 1 every 5k 91 octane since purchase Diablo Trinity with AFM and DoD disabled 91 octane tune Super 10 muffl

Colossus
Colossus

You might be surprised how many dealers out there don't even know an issue with AFM and lifter collapse exists until they get one for the first time. 

swathdiver Senior Enthusiast

swathdiver

Posted
Posted

Dirty oil is AFMs worst enemy.  The lifters and VLOM and other parts have also been updated since it was first introduced making it more reliable.  How reliable?  Well, many people have issues just over the 100K mile mark while others double that without trouble.  It also seems that the system is even more reliable in the Gen V motors. 

 

AFM adds moving parts and moving parts wear out.  A Suburban with a 5.3 is not going to benefit from AFM as much as a Tahoe or regular cab pick up truck as it is much heavier.  There's a saying, by deleting AFM, one gets Gen III reliability with Gen IV durability.

 

Many people disable AFM through a tune or disabling device, the parts are still there and can fail, but still better than if it was operating.  One frustration is that when it usually goes, there's no warning, it starts with a collapsed lifter.

 

In your 2018, I don't think you'll have to worry about it for a long long time.  Keep your oil clean and run Dexos/synthetic, don't switch brands/types which can lead to sludge problems, and change it before 7500 miles, preferrably every 5k miles and call it good.  

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Doublebase Enthusiast

Doublebase

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Posted
30 minutes ago, swathdiver said:

Dirty oil is AFMs worst enemy.  The lifters and VLOM and other parts have also been updated since it was first introduced making it more reliable.  How reliable?  Well, many people have issues just over the 100K mile mark while others double that without trouble.  It also seems that the system is even more reliable in the Gen V motors. 

 

AFM adds moving parts and moving parts wear out.  A Suburban with a 5.3 is not going to benefit from AFM as much as a Tahoe or regular cab pick up truck as it is much heavier.  There's a saying, by deleting AFM, one gets Gen III reliability with Gen IV durability.

 

Many people disable AFM through a tune or disabling device, the parts are still there and can fail, but still better than if it was operating.  One frustration is that when it usually goes, there's no warning, it starts with a collapsed lifter.

 

In your 2018, I don't think you'll have to worry about it for a long long time.  Keep your oil clean and run Dexos/synthetic, don't switch brands/types which can lead to sludge problems, and change it before 7500 miles, preferrably every 5k miles and call it good.  

Thanks. Unfortunately disabling it is not an option at this point - 500/700 miles of commuting per week - but maybe after it's paid off I'll consider it. I'm simply amazed at the fuel economy I'm getting out of this truck; highway with the cruise set is giving me between 22-30 plus depending on the hills...stays in V4 most of the time, and on backroads this thing is doing great. I'm averaging 25mpg in my first 1,000 miles. 

 

I definitely will be running a decent quality full synthetic. I find that when motors age and start getting over that 120,000 mark, the 0w20 tends to burn. Guess I'll worry about that bridge when I cross it. But I'll keep my intervals to 5,000 miles (experimented with longer intervals in the past and it did my engine no favors long term).

 

I need to make a decision on when to have my first oil change done, I'm a little over 1,000 miles right now, not sure I'm comfortable going much further with some of the metal particles that are in that oil from the break in process.

swathdiver Senior Enthusiast

swathdiver

Posted
Posted

I think you're fine to keep it active and to change your oil soon and set up 5k mile intervals.  Most folks do this and use Mobil One synthetics.

WesternMike Enthusiast

WesternMike

Posted
Posted

115,000 on my 14 with not a single problem, like not one issue at all with this truck.

Mobi 1 every 5k
91 octane since purchase
Diablo Trinity with AFM and DoD disabled
91 octane tune
Super 10 muffler
Cold air Intake

Run the sea foam every oil change or two as well, will only help! YouTube the process.

If we look after these trucks like we do our bodies.. they will last.

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  • 4 weeks later...
greyjimmy Enthusiast

greyjimmy

Posted
Posted

That mileage is incredible.  My 2015 gets an average of 17 mpg.  Rarely gets over 21 even on the highway.  Has there been a significant change in three years?

I bought it two months ago with 60,000 miles and at 62,000 the #7 cylinder lifters collapsed.  Dealership was great though, towed it and turned it around in three days.

  • Like 1
Doublebase Enthusiast

Doublebase

Posted
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Posted
21 hours ago, greyjimmy said:

That mileage is incredible.  My 2015 gets an average of 17 mpg.  Rarely gets over 21 even on the highway.  Has there been a significant change in three years?

I bought it two months ago with 60,000 miles and at 62,000 the #7 cylinder lifters collapsed.  Dealership was great though, towed it and turned it around in three days.

I don't think there's really been a change, not sure. My buddy has a 2014 and he asked me the same thing, but I've driven his truck before and averaged 24 with it no problem. I think it's just driving tendencies.

 

Weather plays a huge roll in it too - if it's under 40 degrees my mileage drops 2 mpg's.

  • 5 months later...
2018chevysilverado New Member

2018chevysilverado

Posted
Posted

I got a brand new 2018 Silverado and got halfway home after leaving the dealership for the first time and it drove terrible and went back to the dealership and cometo find out the lifter in cylinder 7 had collapsed. It had about 40 miles on at that time. It's insane that it can happen that early

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Centex14 Enthusiast

Centex14

Posted
Posted

I get 20mpg easy on the highway with dod//afm disabled.

Almost a 120k miles with no issues. Dod//afm disabled for the last 4K.


2014 z71 LTZ
Volant Intake
Borla Exhaust
Diablo
Bilstein 5100
Rough Country Level

  • 7 months later...
Eileen Droese New Member

Eileen Droese

Posted
Posted
On 11/17/2018 at 6:09 PM, 2018chevysilverado said:

I got a brand new 2018 Silverado and got halfway home after leaving the dealership for the first time and it drove terrible and went back to the dealership and cometo find out the lifter in cylinder 7 had collapsed. It had about 40 miles on at that time. It's insane that it can happen that early

I just got a brand new 2019 Silverado 5.3 it has 700 miles on it, we’ve had it for 2 weeks and it’s in the shop because lifter 4 collapsed. It’s very disappointing, I have had Chevy trucks since 1990, never had any problems

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Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted

Ever notice that the people reporting disaster do so on their first post? No just a bad lifter but one out of the box. 40 miles, 700 miles. Driving out of the lot. :rolleyes: Pattern? :P Just an observation. Then poof, their gone never to be heard from again...until now...cornered. 

  • Like 1
KARNUT Senior Enthusiast

KARNUT

Posted
Posted

I bought a new 94 dodge diesel 1 ton. Wasn’t my first. First automatic diesel. Before 1K miles the transmission lines came apart. I would have went online to an enthusiast site if I could. As I did with my other rides up to my 14 GMC. It’s not un common especially if there’s a problem, misery love company.


Sent from my iPhone using Tapatalk

3tspapat Enthusiast

3tspapat

Posted
Posted

So of all of the GMs produced with AFM and is currently out on the road, what is the percentage of ones that have failed so far? 

Paintor Enthusiast

Paintor

Posted
Posted
10 hours ago, 3tspapat said:

So of all of the GMs produced with AFM and is currently out on the road, what is the percentage of ones that have failed so far? 

Ask Melling. They make the lifters. They say allllllll the failures are from oil pressure dropping below....read:

 

https://www.melling.com/wp-content/uploads/2018/03/Melling-tech-bulletin-on-GM-LS-Deactivation-Lifter-Issues-3.1.18-1.pdf

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