2019 GMC AT4 6.2 10-speed Lifter failure. (DFM)

carpendj · July 5, 2020

6 month old AT4 with the 6.2 and 10-speed (DFM)

7500 miles

Took it in for its first oil service and to address a couple of other items that I have been waiting on getting resolved due to COVID-19.

Told the dealer that I was hearing a sound from the outside that had me thinking something was wrong.

Sound reminded me of having cheap lower octane gas in a vehicle or trying to drive up an incline in a manual using say 5th when you should be in 3rd.

Truck drove fine and I've been seeing 19-22 mpg consistently.

GMC dealer checked it out and said it sounds like one of my lifters has failed.

They now have to strip the engine to determine how bad this is.

I had 2015 RAM for almost 5 years. Despite grief from Chevy/Ford owners telling it was going to be a nightmare it ran flawlessly. Never let me down once.

My first GMC and its now sitting waiting on the engine to be stripped so that they can determine what needs to be replaced.

Very disappointed because I love this truck.

This problem had me googling around and finding similar issues on older GMCs but none for the newer 2019+ with DFM.

I wonder how many others of you are impacted?

I only discovered this because I've been driving for 31 years and heard a sound that told me that something was not right.

I think the DFM masks the issue because you get used to it shutting down cyls and just accept that this is the way it is.

No mis-fire sounds at all.

Just sharing this with others.

Get your 2019+ checked out before it hits you outside the warranty.

I am waiting on Range Technology to make their DFM disable tool available for trucks with the 10-speed.

JimCost2014 · July 5, 2020

3 hours ago, carpendj said:

6 month old AT4 with the 6.2 and 10-speed (DFM)

7500 miles

Took it in for its first oil service and to address a couple of other items that I have been waiting on getting resolved due to COVID-19.

Told the dealer that I was hearing a sound from the outside that had me thinking something was wrong.

Sound reminded me of having cheap lower octane gas in a vehicle or trying to drive up an incline in a manual using say 5th when you should be in 3rd.

Truck drove fine and I've been seeing 19-22 mpg consistently.

GMC dealer checked it out and said it sounds like one of my lifters has failed.

They now have to strip the engine to determine how bad this is.

I had 2015 RAM for almost 5 years. Despite grief from Chevy/Ford owners telling it was going to be a nightmare it ran flawlessly. Never let me down once.

My first GMC and its now sitting waiting on the engine to be stripped so that they can determine what needs to be replaced.

Very disappointed because I love this truck.

This problem had me googling around and finding similar issues on older GMCs but none for the newer 2019+ with DFM.

I wonder how many others of you are impacted?

I only discovered this because I've been driving for 31 years and heard a sound that told me that something was not right.

I think the DFM masks the issue because you get used to it shutting down cyls and just accept that this is the way it is.

No mis-fire sounds at all.

Just sharing this with others.

Get your 2019+ checked out before it hits you outside the warranty.

I am waiting on Range Technology to make their DFM disable tool available for trucks with the 10-speed.

Welcome to the site.

Why did you just ship from Dodge?

carpendj · July 5, 2020

I do not understand the question about ship from Dodge? Do you mean why did I select a GMC vs a new RAM?

Mikedfw · July 5, 2020

Think he meant jump ship. Was probably a typo or auto correct. But yes, why did you leave dodge for gm

Sent from my SM-N960U using Tapatalk

EXSlider400 · July 5, 2020

Before letting them open up a new engine, I would have another dealer look at it. The noises with these new engines from the DI and DFM do sound like lifters. With that low of miles I would wait to see if it gets worse.

carpendj · July 5, 2020

4 hours ago, Mikedfw said:

Think he meant jump ship. Was probably a typo or auto correct. But yes, why did you leave dodge for gm

Sent from my SM-N960U using Tapatalk

Great question. It was simply time to replace my truck and I wanted something different. My initial focus was on a Chevrolet Trail Boss and due to having a relationship with a local Chevy dealer, I managed to get an extended weekend with a 5.3 Trail Boss that had the 8-speed. While I loved the look of the truck and I so badly wanted to love it, it did not excite me at all. My HEMI 5.7 with the 8-speed drove much better than the 5.3 with the 8-speed. My local RAM dealer told me to try a Rebel and so I did and managed to get that for a long weekend. It does not look as good as the Trail Boss but driving it was a big improvement on the Trail Boss and my own 2015 RAM. The Rebel felt like a much classier vehicle than the Trail Boss, but for me, it was another RAM and I wanted to try something different. I held off and waited for the Chevy 5.3 Trail Boss with the 10-speed and once again, felt disappointed in the way it drove. At that time the 6.2 Trail Boss was talked about but not yet available. The AT4 seemed overpriced and much more than I wanted to spend. Despite this I gave it a try and loved it. For sure it is not perfect. The front seats are way to firm and uncomfortable and it does not corner like the RAM. But that 6.2 and 10-speed are just awesome. I was happy getting 17-18 mpg on average in my RAM but in this AT4 I am easily getting 19-22 mpg. I hated the cylinder deactivation in the RAM and would turn it off but I've not felt the need to get upset with the DFM in the AT4 (until now). I love the little things like the heads up display, the 360 cameras and that tailgate. Getting $10,500 off MSRP made it affordable. I never considered the F150 as I could't live with some Ecoboost V6 and the interiors of the Jap trucks looked awful. I've been bragging about this AT4 but are now a little down about it and its the first time I have ever had a new vehicle in all my years of driving that needs such major repair work in the first few months of ownership.

Edited July 5, 2020 by carpendj

carpendj · July 5, 2020

I should add that my local dealer told me that while they have not seen similar problems with 6.2 10-speed DFM models, its been raised by other dealerships. This suggests that others are indeed impacted.

JimCost2014 · July 5, 2020

15 hours ago, carpendj said:

I do not understand the question about ship from Dodge? Do you mean why did I select a GMC vs a new RAM?

Correct.

Sorry, was not paying attention while typing.

BIGDOGx · July 7, 2020

On 7/5/2020 at 11:37 AM, EXSlider400 said:

Before letting them open up a new engine, I would have another dealer look at it. The noises with these new engines from the DI and DFM do sound like lifters. With that low of miles I would wait to see if it gets worse.

I agree, it's best to get it checked out to be sure but do not be super shocked if they tell you working as intended. These di engines at least in the trucks with their granny exhaust note gm has on them are the loudest clickity clackity engines i have ever owned. A box of rocks best describes the sound of a newer gen gm v-8 di engine imo. Imo the oil pump whine is the absolute worst though with these 6.2's, nothing like sounding like a 1985 ford Taurus with a power steering issue.

Edited July 7, 2020 by BIGDOGx

tbare54 · July 7, 2020

There is a recent SERVICE BULLETIN from GM on this problem, I have attached it below.

MC-10176613-9999.pdf

carpendj · July 9, 2020

Finally picked up my truck from the dealer today. They told me that one of the Lifter springs had failed and per a GMC recommendation, they replace all the lifters on that side of the engine. Be warned and keep a watchful eye on similar newer engines with the DFM.

Was not expecting this problem to occur on the newer trucks. Very disappointing.

My truck has 7500 miles but for sure it was happening some months ago. I just decided, with all this COVID-19 stuff, to hang on until my first oil change and get it looked at then.

I am gentle with my vehicles and take great care of them.

carpendj · July 9, 2020

https://static.nhtsa.gov/odi/tsbs/2020/MC-10173397-9999.pdf

gmcsierra71 · July 12, 2020

Here is a link to a post I created in Sep 2019:

Several members had posted that their lifters needed replacing ( one at 1800 miles, another at 5500 miles, another at 3500 miles etc). In my post, I was trying to consolidate this issue from several members. Still wonder how often it happens?

SierraNoob · July 24, 2020

Lifters and dfm solenoid for cylinder 3 are being replace in my 5.3 10 speed currently at 4100 miles

GMCelevation · February 10, 2021

My 2019 GMC Sierra is at the dealer now with a lifter sounds and a misfire with only 12k miles . I wonder if a Range DFM delete will prevent this lifters failure constantly in the future ?