I have a 2017 Chevy Silverado 5.3 engine. Although it’s a V8, it switches to 4 cylinders when the 8 are not needed (an active fuel management system that deactivates cylinders to conserve fuel). I have heard that there have been problems with the lifters (that are not used when in 4 cylinder) don’t get oil and could cause an eventual engine breakdown. How does one evert this problem & do you think that putting a unit plugged into the OBD II slot, to disable the function would, although lessening gas mileage, help alleviate this problem in the long run?
You can get a disabler that plugs into the OBDII port, but I like the plug that fits in the tow hitch that automatically shuts it off when it thinks it's in towing mode.
that towing thing sounds interesting, doc. Can you recommend a product?
It’s definitely wise to turn off the AFM system to improve longevity of the engine. You have several options. The more popular (common) is to purchase an AFM Disabler device from Range Technology ( https://www.rangetechnology.com). They are pretty effective in keeping the vehicle from going into V4 mode. If going this route, I would order direct from Range Technology to get the one with the latest updates as some of the earlier ones could drain the battery if left plugged in but an updated firmware later fixed that issue. Realize this only addresses (via software) one aspect of the cylinder deactivation (AFM) issue and that is it no longer goes into V4 mode. However, the hardware is still present: the lifters themselves can still fail, the solenoids in the Lifter Oil Manifold Assembly (LOMA) can still leak causing lifters to collapse, and there can still be glitches in the software causing the lifters to collapse. These are less common things that could occur but the risk is always there. However, getting rid of these components (DOD delete and a permanent solution) would be a $3,000+ job.
You could also disable the cylinder deactivation via HPTuners software (avoids having an OBDII dongle plugged in all the time). To be honest, if it were my truck and assuming it is out of warranty, this is the route I would go and it’s a cleaner solution than the AFM Disabler dongle. I am not sure what all is involved to purchase the HPTuners software for a DIYer (others have done it so it’s definitely possible), but you could also have the right shop do it for you.
See below: Within HP Tuners there is a tab (Fuel tab) that allows you to disable it. I saw another YouTuber disable it in a similar way: it looked too easy. I just don’t know the details on obtaining the software or how much it costs. A good performance shop should have HPTuners and they can probably turn off the AFM for you. HPTuners is well known and reputable so I would go that route (if out of warranty).
See below at 5:17
https://m.youtube.com/watch?v=Rc8BW18tQeU&feature=youtu.be
Great info.
Yes I would get the AFM system disabled to avoid all the issues that can stem from it. Hate how they don't give you the option to turn it off with a switch or something.
I don't remember where I saw it, somewhere in an online search.
What is the best way to deactivate the AFM/DOD system on my 2018 GMC Sierra 1500 5.3l engine. I only have 34000 miles on it and I'm wanting it to last me a long time.
Thanks D-dubya for doing the homework. The GM 5.7 is not a bad motor but for the cylinder deactivation. For a 2017, the horse is already 6 years out of the barn, but I’d probably do one of those if it was my truck.
The 5.7 predates AFM.
Cylinder deactivation is available on the engines in this article:
https://gmauthority.com/blog/gm/general-motors-technology/general-motors-propulsion-technology/general-motors-active-fuel-management-cylinder-deactivation-technology/