CMoore711
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- Jul 18, 2017
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You will hear many different experiences from different owners.
Is it electrical or mechanical?
The PCM is set up or "tuned" from the factory settings to allow the AFM system to function based a certain set of parameters and inputs experienced while driving to allow the PCM to decide when its ok to run on less than all 8 cylinders, then shutting down half of them and going into 4 cylinder mode to increase gas mileage. Have there been any owners you've heard of saying "Man somethings wrong with my AFM system; It always stays in V8 mode and never goes into 4 cylinder mode?" (or visa versa). How many owners are going to the dealership service department reporting issues of the AFM system not activating or functioning? None that I am aware of... Hell I bet over 60% of the owners don't even know it's happening and just drive around. The point is; Electronically the system works and functions as it should.
What is the weakness and failure of the AFM system? Every failure is always related to the AFM lifters and the VLOM which are both mechanical parts in the engine.
Simply deactivating the AFM system electronically via a tune or Range type device is not a long-term permanent solution. Is it better than doing nothing? Yes. For some owners maybe it is all that is needed, and for other's it's not. Not everyone own's their vehicles for 100K+ miles. There are other variables too such as oil change intervals and driving habits that can contribute to varying individual experiences. It really is a dice roll.
My personal experience in my '15 Yukon XL Denali with 6.2 L86 and 8 speed transmission:
Purchased CPO with 24K miles
Installed Range AFM dissabler device at 32K miles.
Oil changed every 3-4K miles with Mobile 1 or Amsoil Signature.
Had a failed AFM lifter at 78K miles.
Is it electrical or mechanical?
The PCM is set up or "tuned" from the factory settings to allow the AFM system to function based a certain set of parameters and inputs experienced while driving to allow the PCM to decide when its ok to run on less than all 8 cylinders, then shutting down half of them and going into 4 cylinder mode to increase gas mileage. Have there been any owners you've heard of saying "Man somethings wrong with my AFM system; It always stays in V8 mode and never goes into 4 cylinder mode?" (or visa versa). How many owners are going to the dealership service department reporting issues of the AFM system not activating or functioning? None that I am aware of... Hell I bet over 60% of the owners don't even know it's happening and just drive around. The point is; Electronically the system works and functions as it should.
What is the weakness and failure of the AFM system? Every failure is always related to the AFM lifters and the VLOM which are both mechanical parts in the engine.
Simply deactivating the AFM system electronically via a tune or Range type device is not a long-term permanent solution. Is it better than doing nothing? Yes. For some owners maybe it is all that is needed, and for other's it's not. Not everyone own's their vehicles for 100K+ miles. There are other variables too such as oil change intervals and driving habits that can contribute to varying individual experiences. It really is a dice roll.
My personal experience in my '15 Yukon XL Denali with 6.2 L86 and 8 speed transmission:
Purchased CPO with 24K miles
Installed Range AFM dissabler device at 32K miles.
Oil changed every 3-4K miles with Mobile 1 or Amsoil Signature.
Had a failed AFM lifter at 78K miles.
