RA003 Active Fuel Management Disabler Device, AFM/DFM Disabler Device Compatible with most GM V6 and V8 Vehicles

Bought this for a 2015 GMC Yukon XL. The Yukon was sluggish in 4 cylinder mode and did not transition smoothly between 4 and 8 cylinders. We were also having torque converter issues and needed to be able to tell which symptoms were from torque converter issues and which symptoms were just transition between 4 and 8 cylinders. Turns out a new torque converter was needed, but left this plugged in simply for in town driving because of the lugging. So far a slight decrease in mpg has been noticed, but well worth it for nice smooth in town driving. It is also nice on the highway to not have to wait for the truck to switch modes then downshift for acceleration. Would definitely recommend! This seems to do just as good of a job as any other brand would for much less money. Bought this one because of the good reviews and wanted to share that it has been well worth it! Hoping to also save the hassle of doing lifters in the future.

I received this today and couldn’t wait to try it. My 2007 Chevrolet Tahoe has the AFM. Recently it developed a “shuddering” in the engine when slowing down, along with a little feel of a periodic misfire at idle. My mechanic discovered the misfire was occurring in cylinder 4 and was likely related to the shuddering and these were both caused by AFM.Installing is a breeze. However, I did not disconnect the battery as the instructions indicate, but had read other reviews stating they just plugged it in while the engine was off, so I did that. The unit went through a cycle with the lights and then settled on one light on at the end.I let the car sit for several hours as I had some other business to attend to. I then hopped in the tahoe and it fired right up, and took it for a drive.It performed excellent. Love the feel of the V8 all the time. Shuddering completely gone with no V4 at any time throughout the ride. I still felt a little periodic misfire at idle, but that’s likely a lifter that is sticking a bit.My only regret is that I didn’t plug this in at 100,001 miles as I believe the lifter sticking (which is the beginning of the end for the motor) is due to AFM. I currently have just over 200,000 miles on the car and engine and with this device I just might make 300,000.If you’re looking for an AFM Disabler, this is a solid pick at a good price!Let’s see how it does over time….

I am so happy with this thing that I actually could not wait to do this review. Having my 2015 Silverado 1500 Z71 with 5.3 engine for more than a year now, this AFM disabler is the best thing I have done to it. Like many others, at first I thought the AFM function was fairly neat. A way to save a bit of fuel. But, although it is a consideration, do we really buy V8 trucks to go into 4-cylinder mode?As many others have suggested, including the manufacturer’s instructions, I didn’t plug this thing in until I first disconnected my negative terminal from the battery. After that, one push into the OBD port and then reconnect the battery. Took all of 15 seconds. Don’t be put off by the simple packaging and one-page instruction sheet. That is all you need. I let it stop flashing and proceeded to take s test drive.Highway speed or moderate to heavy acceleration was never the problem. My complaint was the transition to 4-cylinder as I drove through the 20mph areas where I live or when gently trying to accelerate after a near stop for a traffic light. That is when the AFM made that annoying pop from the exhaust, custom run duals behind the passenger side rear wheel, and there was a delay in acceleration. No longer! It was immediately better. Drove the same street where it ALWAYS went into half-engine mode but this time the display indicated the V8 was always active. It kept the throaty sound and actually pushed better at slow speeds before I needed a heavier acceleration. As I stated previously, I instantly felt a difference.Now, for the skeptic. I was so very close to getting the Range AFM many times but could never quite bring myself to spend the $190 or so on what I thought was a “maybe it will work” situation. I found this one and, after reading many of the reviews, decided to try it knowing I would return it if it did not work and then buy the more expensive one. I don’t care what it’s branded. I only care that it was approximately $60 cheaper than any other one and that it works exactly as it should.If it fails, I will update this review. For now, though, I am very pleased and will tell anyone that it was the most quickly apparent improvement short of a custom program job or a new set of lifters, cam shaft etc. for my performance. Take it or leave the blue light glow on my foot well. I don’t really care for it so will probably put tape over the LEDs.

I had all the DOD headaches! So I removed the DOD camshaft, lifters, oil feed manifold and plugged all oil galleys that fed the lifters. My engine ran great! However, the ecu on this model cannot be programmed to turn off the DOD. The problem this causes is that the ecu turns off the injectors to the four cylinders when it calls for 4 cyl mode!I was concerned about buying this disabler because although I didn't want the 4 cyl mode to kick in, I DID want the auto stop feature to work. This unit works great! No DOD request from the ecu AND the auto stop feature works perfectly. I am currently getting 19.5 miles per gallon.Don't be afraid of buying it. I've been using it a month now with no problems.

Works exactly as expected. No more AFM on my 2015 Sierra 4.3. It does pull apart easily when you try to take it out. Other than that, excellent.

Works great east to install

It’s only been on for a 20 minute drive, but so far I am extremely happy and it has done exactly what it says it does. I have it on my 2009/10 Australian Holden Commodore 6.0 litre VE SS Ute, and it has stayed on 8 cylinders. I was a little hesitant because there were no reviews from Australia, but I received an answer to a question I asked from a fellow Aussie and that gave me the confidence to go ahead. Delivery was pretty quick too, arriving in half the time it was expected.EDIT February 2022: still working well!

I've had it in my 2018 Silverado for 3 months now, and it performing as advertised. It has decreased my fuel consumption by approximately 2L/100kms as well.

Super easy to use. Just plug it in and drive. Works perfectly. Plugged it in and haven’t had V4 kick in since!!

2014 Silverado still showing v4 as per usual. Dont waste your money