2022 GMC Sierra 1500, 5.3 ECOTEC3 W/O DFM

2022 Elevation · May 18

Is anyone having any engine issues regarding lifters?

davester · May 18

I'm assuming you have a covid truck, where dfm was disabled because of a chip shortage.

If so, then you still have dfm lifters installed, the system is just deactivated. The lifters can still fail, even when they are not being activated.

TrueBlue · May 18

Are there any documented cases of this happening to deactivated DFM trucks?

davester · May 18

documented how? people have posted on forums that their lifters have failed, with them disabled via range-style devices and/or disabled via a tune.

TrueBlue · May 18

Haven't seen those posts yet. Must have missed them if they were on this site.

Also, didn't know you could disable DFM/AFM with a tune.

newdude · May 19

14 hours ago, TrueBlue said:

Also, didn't know you could disable DFM/AFM with a tune.

Been possible since AFM's launch in 2007. HP Tuners, some HP credits and boom its off permanently in the ECM. Its more expensive now though on the 2019-2026 trucks because you have to unlock/swap for an unlocked ECM, and then the amount of credits to tune is much more than the old stuff.

GMCustomerService · June 11

We understand the frustrations that engine concerns bring, @2022 Elevation If you are currently experiencing symptoms of lifter concerns with your Sierra, we would like to learn more. Have you brought your concerns to the attention of your local GMC dealer? If not, we highly encourage you to do so. That said, would be more than happy to provide an extra layer of support in the process. To begin, please visit: https://s.gmc.com/support-request  and fill out the pertinent details in the support request form. This will ensure that your request is routed properly so we may explore the best path of assistance moving forward. We will be sure to keep an eye out for your outreach.

Edited June 11 by GMCustomerService