AFM DFM Disabler AG001 V8 Active Fuel Management Compatible GM Chevy 5.3 Silverado Tahoe Sierra Yukon DOD Non

I have a 2019 Silverado with the 5.3l. This thing works awesome! It’s a fraction of the price of other “name brands” and performs flawlessly! I have full power all the time! My exhaust doesn’t sound terrible anymore! And I haven’t had any issues with engine lights and it simply plugs in to the OBD port and takes care of the rest! Just so everyone is aware. In my truck the power light comes on but the two lights that turn on to tell you it’s communicating with the system don’t come on until I’m in gear and release the brakes. Then all of the lights come on and you will immediately notice that you won’t hear or feel the fumbling of cylinders shutting down. If you have aftermarket exhaust, it will be far more pronounced and noticeable! I’m pumped! I’m hoping that installing this will prolong the life of this engine! I’ve already had it in the dealership for the top of the engine to be rebuilt due to 2 broken lifters that damaged the camshaft. The dealership replaced all of the lifters and the camshaft and I had my truck back for 2-3 weeks and the engine started ticking which got louder and louder within a mile of hearing it going down the freeway before I got to a safe place to pullover and stop. The truck returned to the dealership where they were then forced to replace the entire engine due to metal shavings and debris traveling throughout the engine causing severe damage throughout. Thank god everything was covered under warranty! The two invoices combined were close to $17,000! I’m hoping this little thing not allowing the system to shut cylinders down will prolong the life of this engine so I can keep this truck for quite some time!

It has worked well for the past few months. It seems like a quality product. It does what it says it will do.

### The Best Insurance You Can Buy for Your GM Vehicle If you own a GM truck, SUV, or car with the AFM (Active Fuel Management) or DFM (Dynamic Fuel Management) system, you know the dread. The constant switching between V8 and V4 mode is not only annoying, but it's a ticking time bomb for your engine. After researching the countless horror stories of lifter and camshaft failures, I decided to be proactive and get a disabler. And I'm so glad I did. This little device is a game-changer. Installation is literally as easy as plugging it into the OBD-II port under the dash. That's it. There's no wiring, no tuning, and no permanent changes to your vehicle's computer. The moment I started the truck, the difference was immediately noticeable. The most significant benefit for me is the **elimination of the "shudder."** The annoying vibration and hesitation that came with the V4 mode is completely gone. The engine now runs and sounds like a proper V8 should—smooth, powerful, and consistent. The throttle response is also much better, and the transmission shifts more predictably without the constant hunting for the right gear. While some might worry about a drop in gas mileage, I haven't noticed a significant change. What I have gained is peace of mind. For a fraction of the cost of a lifter replacement job (which can run into the thousands), this disabler is the best insurance you can get for your engine. It's a simple, effective, and fully reversible solution to a well-known and costly problem. I wish I had bought it sooner.

Works perfectly with no brainer easy installion. My GMC Sierra AT4 no longer idles down at stop lights and full power is immediately available when foot presses accelerator which is important when pulling a trailer or boat.

Works as expected. Took 2 seconds to install.

It was an easy plug-n-play. It does effect gas consumption. Rightfully, because it turns off the fuel flex V-4 and keeps it open on V-8 mode. No More lag for power, and piece of mind, knowing that the rockers won't get locked in the open or closed positions. Which can cause greater issues. Possibly having to take off the top end to reach the piston rockers and reset them. And the damage it could cause the cylinders. Plus a top end removal and rebuild with labor can cost up to 4k$.

Works as described, plug and play

It's only been 2 days...but I am super pleased with it. Took it out the package, plugged in to the truck and boom!!! 5.3 running much better, no more funny shifting and engine shutters. Please read the instructions when you get yours. It does mention that it may drain a battery on a vehicle. Make sure you read up and then...enjoy! Sooooooo...giving an update on this item after using it for several days now.. This thing is a battery killer! I'm going to go ahead and replace my battery, it's 3 years old. But if the new battery doesn't help my situation, I will probably toss this one in the glove box and purchase another. I've been ruined, the truck drives so much better with the fuel management system disabled. Surely I can find one of these that won't drain my battery.