Range TechnologyRA003R Plug & Play AFM/DFM Active Fuel Management Disabler (Package may vary)

If you are having AFM/DFM issues like we have all had in our GM vehicles, this is the device you want. How it compares to other manufactures of similar devices, I cannot comment on. However, Holley Performance, who I believe is the parent company who manufactures these devices, is the best name in the business when it comes to anything and everything tuning related.This device is beyond easy to use as you simply plug it in, and forget it. Instead of the jerky shifting between V8 and V4 cylinder modes in my 2015 Silverado, it keeps my truck in V8 mode all the time. Gas mileage may be slightly worse, you're driving a V8 pickup, but who cares. Not having to (hopefully) not rebuild the top end of my engine when the lifters collapse again will pay this little gadget off 10X over again. I would highly recommend this to all GM truck owners with the 5.3 to delete V4 mode.

Works perfect in my 2019 silverado, hasn’t killed the battery yet and it’s definitely sat for a few days in a row. Also I’m not sure why but I’m averaging a little better mpg which really doesn’t make sense. I do very little to zero highway so maybe that’s why

Easy to use, its servers its function with no lag of speed. Doesn’t change any computer programming permanently or cause any engine lights. Decent price for the quality.

Somehow increased fuel efficiency while decreasing the weird transmission clunking caused by AFM mode switching. Hopefully this adds some life to the engine.

Shipping was faster than they stated. However l returned the item without using it. Didn't like it wore battery down as this was being put in a car driven maybe 1 every 1 or 2 weeks. So l had the AFM disabled while a performance shop was in the ECM doing a tune.

Bought this for my 2019 GMC Sierra Limited. After buying this truck, I noticed when driving from a stop the truck hesitates and sometimesthe shift from V4 and V8 made itself known. Also noticed a big jolt the first 2 shifts after turning the truck on and pulling out of the driveway. So I bought this product the save my engine and transmission. Holy crap, I am blown away. Truck takes off with zero hesitation full power and no more hard shifts at anytime. Feels like a true V8 should. I lost 0.5 MPG which is well worth it. Don't wait on buying this. Get it asap.

So far so good. It functions as described. Side benefit is that shifting has improved greatly. I'm not sure why that is. Prior to using this my transmission would clunk in the gear or hesitate shifting. I assume that was the computer trying to decide whether to use V4 or V8 mode. My suburban drives so much better now. There may be a fuel economy hit but I'm sure it will be minor. It would probably matter more if you drive mostly on the highway.

It plugs in easily but I read it will drain the battery if the truck sits too long so I have to take it out too often.