Active Fuel Management (AFM) and Dynamic Fuel Management (DFM) will not be available on certain 2021 model year Silverado 1500/Sierra 1500 pickups

[repairman54]

Traded my '11 Tahoe 5.3 in for the '23 Silverado. Tahoe had 150k on it, got it at 35k and ran the Range AFM disabler on it the whole time I had it. I read about the lifter issues back then, always ran full synth. oils and AC UPR filters changed via the OLM at 10%.

19 highway was the best it would do, 20 without it. Only engine part that failed in the whole time was an erratic MAP sensor. 

I'm not worried about the new trucks 6.2 failing. Just going to up to 5-30w oil instead of the 0-20w for summers. 

[A321Driver]

So from what I have read my 2021 has the deleted DFM system via the ECM.  All the DFM fuses, wiring, and associated hardware is installed.  My questions is, what are the odds of the hardware failing if the is not being used and essentially locked in the DFM off position?

 

I'm deciding whether to turn the lease in or buy and run it as long as I can.

 

any easy way to disable the auto start/stop?   I'm getting tired of having to hit the button every time I get in the truck.

[SPASierra]

On 4/26/2023 at 8:59 PM, A321Driver said:

So from what I have read my 2021 has the deleted DFM system via the ECM.  All the DFM fuses, wiring, and associated hardware is installed.  My questions is, what are the odds of the hardware failing if the is not being used and essentially locked in the DFM off position?

 

I'm deciding whether to turn the lease in or buy and run it as long as I can.

 

any easy way to disable the auto start/stop?   I'm getting tired of having to hit the button every time I get in the truck.

You can buy the AutoStop Eliminator.  There have been reported lifter failures on trucks that didn't have AFM/DFM enabled, but they are rare. 

 

 

[Offroad9730]

On 3/15/2021 at 11:06 AM, Daly said:

My question is that if AFM/DFM is so great for fuel economy, why was it the first system to be dropped? Why not other systems, like LED lights, or wireless carplay, or park assist. Or maybe it's because AFM/DFM really doesn't do much and won't be missed much. 

It's because it destroyed lifters and cam.  Regularly.  POS.  IT WILL NOT BE MISSED...............IF.........they do indeed  delete it. It's a money maker in the service dept.  BIG BUCKS to fix at a dealer.

[Offroad9730]

On 3/15/2021 at 7:07 AM, MS3DALE said:

For those that do not like AFM/DFM, You will be able to buy certain 2021's without it....

 

2021 Silverado 1500 and Sierra 1500 pickups

 

As promised, we want to continue to keep you in the loop regarding the global, industry-wide shortage of semiconductors.  Today, due to this shortage, we are announcing a new change to select light duty full-size pickup powertrains.  Active Fuel Management (AFM) and Dynamic Fuel Management (DFM) will not be available on certain 2021 model year Silverado 1500 and Sierra 1500 pickups.  By taking this measure, it will enable continued production and delivery of inventory to help respond to the strong customer and dealer demand for our full-size pickup models as the industry continues to rebound and strengthen.

 

L82 - 5.3L EcoTec3 V8 w/6-speed Automatic Transmission (MYC) & L84 - 5.3L EcoTec3 V8 w/8-speed Automatic Transmission (MQE) (only):

For orders with a scheduled production date on or after March 15, 2021, GM will build most L82 engines on 1500 pickups without AFM (refer to the updated Order Guide and table below for trim details).  Similarly, for orders with a scheduled production date on or after March 29, 2021, GM will build most L84 engines on 1500 pickups without DFM (refer to the updated Order Guide and the table below for trim details).   Any sold orders of these affected pickups which have not been entered in the Production Order Management and Scheduling system by March 16, 2021 will be built without AFM or DFM.  The dealer has the responsibility to and must advise affected sold order customers immediately.

 

Pickups with 5.3L V8s which are built without AFM or DFM, as applicable, will include a new RPO code added by General Motors: “YK9 – Not Equipped with Active Fuel Management" or “YK9 - Not Equipped with Dynamic Fuel Management". This RPO code will be reflected on the Dealer Invoice along with an associated $50 MSRP credit.  The Monroney label will include this credit and indicate that the vehicle was built without AFM or DFM.  These 2021 Silverado 1500 and Sierra 1500 pickups which are built without AFM or DFM, will also receive revised EPA certified fuel economy estimates.  Chevrolet and GMC are updating all consumer and dealer facing communications as appropriate.  In addition, dealers are strongly urged to counsel directly with all customers who purchase affected vehicles to ensure each customer understands its vehicle content and fuel economy.  This change to the availability of AFM and DFM on the 5.3L V8 is currently expected to remain in place for the remainder of the 2021MY.  A listing of affected trims is listed below and is subject to change by General Motors:

 

[Offroad9730]

Does GM still use cylinder deactivation?

 

 

Apparently GM is back in full swing manufacturing new 5.3's with Dynamic Fuel Management (DFM), which shuts down cylinders randomly. I'm not at all thrilled to learn that my brand new 2023 GMC 1500 came with DFM. (recent quote)

[badtenant]

I have a 2021 Custom Trail Boss with AFM (L82).  There is nothing on the dash nor does the engine sound or feel any different when I'm driving.  How do I know if the AFM is actually activated?  It was pretty noticeable on my previous AFM engines.  

[redwngr]

 

 

1 hour ago, badtenant said:

I have a 2021 Custom Trail Boss with AFM (L82).  There is nothing on the dash nor does the engine sound or feel any different when I'm driving.  How do I know if the AFM is actually activated?  It was pretty noticeable on my previous AFM engines.  

Does your QR code show rpo code YK9?

 

If it does, it is one of the ones that doesn't have the electronics to run cylinder deactivation.

 

 

 

 

[badtenant]

I don't have the QR code on my truck.  When I run the VIN in TDS it does not show the YK9 RPO.  

[Silver Yeti]

My 2021 Silverado 1500 RST with the 5.3L (L84) engine came with DFM, but thank God for the "Range" AFM/DFM disabler module, which plugs right into the OBD-II maintenance port.

 

The best $300.00 I ever spent.

 

Range Technology RA003B AFM/DFM Disabler

Edited June 11 by Silver Yeti