Made without AFM module

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kurtibm

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General Motors has decided to make some 2021 full-size pickups without a certain fuel management module because of the ongoing microchip shortage. As a result, those trucks will get around one fewer mile per gallon of gas, meaning they’ll burn more fuel to go the same distance, releasing more carbon emissions into the atmosphere. (But maybe more MBLF (miles before lifter failure)).

The trucks affected are models that use GM’s 5.3-liter EcoTec3 V8 engine (including versions with six-speed or eight-speed automatic transmissions), according to Reuters, which first reported the decision. That includes the popular Chevy Silverado and GMC’s Sierra.

The module is what powers the trademarked “Active Fuel Management” or “Dynamic Fuel Management” systems GM promotes on these trucks, which deactivates some of the engine’s cylinders to boost fuel economy. A company spokesperson told Reuters that the decision would affect GM’s fleet-wide average fuel economy, but that it wouldn’t be a “major impact.”

GM decided to make the trucks without the fuel module so as not to affect production.

We can only hope that Tahoe & Yukon are included.....
 

21TahoeDisappoint

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I have a neighbor who ordered a Suburban without AFM (his choice). Wasn't aware that was something one could do.
 

Toomanyhobbies

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I read somewhere that the same lifters go into the block whether or not AFM is equipped. Anyone know if this is true?
 

OldBob

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I was hopeful someone would have responded with some more on this. I looked at a used 2021 Sierra today. The original window stick has a -$50 for no AFM and was wondering if the lifters were still in it.
 

B-train

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They are all built with the same lifters. As @03catburban said, its the non-activation that is the good part. Doesn't mean they won't fail, but should make it less likely. Change your oil every 5k with a good filter and you should be golden
 

swathdiver

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I was hopeful someone would have responded with some more on this. I looked at a used 2021 Sierra today. The original window stick has a -$50 for no AFM and was wondering if the lifters were still in it.
All the AFM components are there it is just not active. This is fine and is no more unreliable than the regular lifters.

The majority of the time, the lifters break when the VLOM solenoids get out of time.
 

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