FREE DFM & AFM Disable! Chevy & GM 5.3, 6.2 Owners Watch This!

🔥 Disable DFM & AFM? Try This Simple Trick! 🔥

If you’ve been frustrated with Dynamic Fuel Management (DFM) or Active Fuel Management (AFM) in GM small-block engines, you're not alone! 🤔 Many drivers want to turn it off—but is there a way to do it without buying a delete device?

🚗 The Answer? Driving in L9, L7, or L5!
Since creating this video, I feel confident that shifting into L9, L7, or L5 (depending on your transmission speed) will disable DFM & AFM, letting you drive in full V8 mode! I put this theory to the test and show side-by-side footage comparing DFM vs. L9 mode. The difference is HUGE!

⚙️ What You’ll Learn in This Video:
✅ What DFM & AFM actually do in GM engines
✅ Why some drivers experience issues & want to disable them
✅ A real-world test: DFM vs. L9 Mode – does it actually work?

💡 I’m not a mechanic—just an enthusiast who loves researching and testing solutions! If you're curious about DFM, AFM, and how to get the best performance from your GM engine, this video is for you.

🚀 WATCH NOW & SEE THE RESULTS FOR YOURSELF!

Footage comparisons timestamp from 10:45-15:40

Article referenced explaining DFM :

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#gmc #chevy #dfm

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Music Credits:

Creative Commons Attribution-ShareAlike 3.0 Unported

[Donslife]

linktr.ee/donslife - Links to all of my products and discounts

[kennethlevan]

I've been driving and loving my 2020 6.2L GMC Sierra for a couple years. But now that I know about L9, I love it even more. Can't believe GM engineers designed a way to degrade power and the owner's driving experience. If I gave a crap about fuel economy, I'd be driving a Prius. Thanks Don!

[eliaschaya]

My god, thanks for the video, I was going crazy with the shudder I was experiencing, driving my new 2024 Escalade between 35mph and 40mph.The dealer said it was normal. I went out after watching this video and put the gear on L9 and wow no more shudder. Thanks for the information, can’t believe the dealer did not tell me about this.

[Redfishdaddy]

Well I tried it and it works, I have the 5.3 and the 8spd. The other thing I noticed was the automatic stop didn’t work. I did not have to shut it off as I do daily. I drove in L7 first and noticed the immediate difference, then drove in L8. Works the same. Thanks for the heads up.

[wrifeiv]

from what I have deciphered from internet and driving with my 2021 6.2 high country, I've noticed the exact same thing. shifting was better in low gears with L9 and didn't notice much difference in mileage. did the exact same thing with going into reverse isn't used to the last click yet. thanks for the vid, I don't know why nobody "officially" can give us the answer from GM or any other source close to the company. when I bought my truck last year, I complained about the transmission shifting too quickly and nobody had even heard of using the L9 as a work around.

[twoshort]

I just picked up a 2021 Suburban RST with 5.3L and 30k miles. I’ve had it at the dealer twice for a very annoying chirp when downshifting and squeal when at low speed/rpm. They can’t replicate it enough to diagnose it. Based on your video I just tried the L9 trick and it was like driving a different vehicle. Nice and quiet!! Thank you!!

[vance]

This is not actually a new thought but glad you have brought it up on the new style trucks. I have been doing this for a few years on a 2008 5.3 with the 4L60e. I found a few years ago if you stay in drive instead of overdrive the cylinder shut off doesn’t kick in. You can tell it doesn’t from the sound of the engine and also if you set your fuel average to instant economy you will see it doesn’t fluctuate from V8/V4 on the dash like it does in overdrive.

[phillhuddleston]

Anyone else miss thesimplicity of the older trucks eighties and earlier?

[patrickbrennan]

I have a 17 Sierra & I have a info center between ROM & MPH, if you bring up the fuel economy screen down in bottom right you’ll see V8 if your in L5 or L9 it doesn’t change at all unless your in D or L6/L10 then you will see it change to V4 so your assumption is correct, Thanks for the info

[Drsnafubar]

Thanks for the heads up. I bought a Chevy 1500 with a 6.2 last month and didn't even know about dfm.

[JPLaw-smkv]

I’m very very rarely comment but I just wanted to say that guy did a fantastic job. Well articulated well informative didn’t waste any time. Well done

[joeyg]

I have a 21 Tahoe High Country 6.2 After much research I wound up purchasing a Borla Touring cat back system. The look of the system was great. However if not in L9 - the sound was terrible unless you were ON the gas! I got tired of switching to L9 every time, and got annoyed with the sounds. So I returned the system

This video is spot on by the way

[bakerbrook]

I tried running my Elevation 8 spd in L7, but I bought the Pulsar LT, and now I love my truck again. No more auto start-stop, and all the vibration is gone. YAYYY! I was ready to trade it in, but I love it again, and I get to keep it.

[festerrage]

If all you do is to turn off the AFM/DOD electronically without replacing the lifters with normal lifters there is still a good chance that one of the "spring" (my term) listers will fail and lock up causing a missing cylinder and ruining the engine. The best thing to keep things ok for long term is to make sure oil changes happen REGULARLY at 3000 miles regardless of recommendations. I saw what infrequent oil changes and maintenance did to a 2009 LM9 5.3l and it was obvious that the stock lifters (AFM/DOD) would eventually lock up whereas the non AFM/DOD lifters were a lot less likely to fail. Of course, the electronic/ computer solutions to shutting down the AFM/DOD are better than doing nothing (and typically will not trash the warranty (of that's a factor for you). There's a lot more to this but my finger is tired 😂 and I've got to find a new engine 😢. I still love the ls engines! Good luck with this everyone.

[caseykursave]

I'm glad I don't have to deal with that. I ordered mine in July and got it Sept 4 21. 21 Sierra X31 5.3 with no cylinder shutdown and I'm averaging 19.5-20 mpg in Southwest Wisconsin. I feel the cylinder shutdown on any vehicle is just a horrible idea.

[dmmjq]

So I tried this test.. seems like Drive and L10 were the same.. coasting at 50 mph letting off the gas for a few seconds then stepping on the gas I noticed there was a bump a hesitation and then the motor kicked in.. driving in L9 with the same thing letting off the gas for a few seconds then stepping on the gas there was just a hesitation then the motor kicked in ..with no bump.. my guess is the bump may be the cylinders firing back up before kicking in.. so something definitely happening here my guess is GM programmed this on purpose maybe for some kind of diagnostic test if there's a problem with the DMF.. I've also seen videos where if you do a tune you can eliminate the DMF as well as the auto stop and the speed limiter... another great video thanks Don

[drowsy]

Agree. Turn OFF (or disable) AFM/DFM to save the engine. This can be done via gear shifter change or a Range module from Amazon. Keeping a V8 "a real V8" is most reliable in the long run....

[lukeh]

When towing my camper while stock it’d kick into “V4” prematurely so I felt... I now use a superchips programmer to turn off the AFM/DOD and set certain other parameters... the 91 octane tune works great as does the towing tune... I’m cheap but this makes me happy.

[kevinfowler]

I’m a new to me AT4 6.2 owner 2022. First big V8 in a very very long time.
I could hear, without understanding, what this video is all about. L9 is gonna be a must do for a few months, thanks for this

[Prfessor_P]

Currently have a 2021 5.7 Hemi, switching to gear 8 (in Ram's case) gets rid of cylinder deactivation. Looking at buying a RST with the 6.2 and I'm glad to see this can be done on a Chevy as well. Thanks for the video👍👍