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Question about the GMC 5.3 with AFM

Discussion in 'Chainsaws and Power Equipment' started by ThomH123, Mar 15, 2025.

  1. ThomH123

    ThomH123

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    I hope this is the proper place for this question. I recently purchased a GMC 1500 pick up with the 5.3, it runs great and has just under 97,000 on it. Should I buy a “dongle” to disable AFM? If so do you have any recommendations. We all seem to be knowledgeable here so I trust and appreciate any responses.
     
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  2. brenndatomu

    brenndatomu

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    Personally, I delete/disable anything I get that has that crap on it, it's nothing but trouble, sooner or later. At 97k I'd call that "on borrowed time" and do it asap.
    A good place to find out what all the potential issues of it are is on the truck forums, but some are better than others, and I'm not a GM guy, so I dunno which ones are legit, and which ones just have a bunch of trolls looking to stir up drama/hear themselves talk.
     
    Last edited: Mar 15, 2025
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  3. Smokinpiney

    Smokinpiney

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    ThomH123 with that low of miles you might be alright by just disabling the afm. The absolute best way to do it is to do a full delete with new cam and lifters and a tune. That can run you between $1500-2k for parts and a tune if you do it yourself. If you have a shop do it, labor can run ya anywhere between $1-3k on top of parts.
     
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  4. farminkarman

    farminkarman

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    Agreed, I would get rid of the AFM lifters before they trash the engine.
     
  5. Creekin

    Creekin

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    Few years ago my dad's 2013 gmc had a lifter go down, I ended up just replacing the cam and all the lifters with normal lifters
    Cam I replaced with the 4.8l cam of the same year, specs were close enough that wouldn't have to retune the calibration
    Used hp tuners to delete the cyl deactivation

    Last shop I worked at we just deleted it from the pcm without physically doing anything else, seemed to work
     
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  6. Brad M

    Brad M

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    I have a 2008 Chevy Silverado with a 5.3. I disabled the AFM 9 or 10yrs ago with the module shown below. I don’t remember much about researching that brand or if they are still in business it it seems to have worked well for me. 14F89018-F3D6-4C77-937A-9E4B70C308FB.jpeg
     
    Last edited: Mar 16, 2025 at 1:05 PM
  7. BuckeyeFootball

    BuckeyeFootball

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    Yup my BIL is a GM mechanic and tells everyone this.
     
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  8. Brad M

    Brad M

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  9. Ron T

    Ron T

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    Range makes a plug and play that shuts down the afm. I've had mine in several trucks now and it's always worked well
     
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  10. ThomH123

    ThomH123

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    The truck has a 6 month 6000 mile powertrain warranty so for now I will just do a module. Come fall I will probably swap cam and lifters.
     
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  11. Horkn

    Horkn

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    The AFM was/ is one of the worst things GM has done. Any way to disable it is a good idea.
     
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  12. ThomH123

    ThomH123

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    In GM’s defense, government bureaucrats at the EPA have forced vehicle and other manufacturers to go to dire straits. Look at what they did to something as simple as a fuel can.
     
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  13. Horkn

    Horkn

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    I have one of those fuel cans. It takes an engineering degree to use it :rofl: :lol:
     
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  14. ThomH123

    ThomH123

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    I have an EE degree and I keep my old fuel tanks.
     
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  15. Mrxlh

    Mrxlh

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    2020 T/Ahoe with the 5.3 DOD, zero issues with 110,xxx on the clock, what am I doing wrong? :whistle:
     
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  16. BuckeyeFootball

    BuckeyeFootball

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    They may of updated the lifters at some point idk all Ford here.
     
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  17. Horkn

    Horkn

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    Now if only you had a mechanical engineering degree ;)

    Honestly, once you figure it out, mine was given to me by someone that didn't rtfm, they are pretty nice despite being way over engineered.
     
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  18. Horkn

    Horkn

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    You might have bought one that was good. ;)
     
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