Range Technology Offers AFM/DFM Disabler For General Motors Vehicles
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Automotive electronics company Range Technology has released its new Active Fuel Management/Dynamic Fuel Management disabler for General Motors vehicles.
The AFM/DFM disabler is a plug-in module that deactivates the AFM and DFM systems in V6- and V8-powered GM vehicles. The module simply plugs into the vehicle’s OBD-II port, making it easily reversible and ensuring it does not void the vehicle’s warranty.
Range Technology says its disabler will prevent the “shuddering” that some customers experience as AFM/DFM vehicles switch between running on half or all cylinders.” The company also says the module can save the owner money on “costly future repairs,” as GM’s “troublesome valve lifters will no longer be tasked with activating and deactivating constantly.”
General Motors’ DFM technology, also known as Dynamic Skip Fire, saves fuel by only using the cylinders of an engine that are required during the specific driving situation. If a V6 or V8 engine is just cruising down the highway, for example, it will activate DFM. When towing, accelerating or performing other strenuous tasks, the DFM system will remain off, giving the driver full engine power.
DFM is the more advanced successor to AFM. Whereas AFM would flip between four and eight-cylinder mode, DFM shuts down certain cylinders based on the driving scenario. An engine with DFM has 17 different cylinder configurations and will flip between them to deliver an optimal balance between performance and fuel economy.
Range Technology’s plug-in disabler works with older General Motors vehicles that still have AFM and new ones that use DFM. It will work with all GM vehicles with a V6 or V8 engine with AFM or DFM, including cars, SUVs and the popular Chevrolet Silverado and GMC Sierra pickup trucks. Prices start at $189.00 USD.
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Had a Range product for our old Silverado. It works exactly as advertised for the 5.3L engine.
The HD Silverado in the picture has either the 6.6L V8 gasser or the Duramax diesel. Neither has any kind of cylinder deactivation.
Interesting. Working at a Volvo/Mazda store, they both also use some form of fuel saving tech. The Volvo just uses the engine start/stop which totally sucks. Mazda uses something similar to what they are talking about above. It’s (thankfully) not nearly as obnoxious as the engine start/stop, but you can feel a slight shudder-like moment as it starts/stops some cylinders. As normal, Mazda is kind of late to the game here, so I’m not sure if they have had any complaints about it, but I do know people test driving them can feel it and will ask about it. I remember the Cadillac V8,6,4 back in 1981. An engine feature way ahead of it’s time that had issues and they only had it for 2 or 3 years total (first year on all V8 Cadillac’s and then just on the limo’s for another year or two).
I think people wanting to bypass these systems only shows that unless gas is well above $4.00 per gallon, people don’t want the tech.
Cadillacs v8-6-4’s were super reliable engines that almost never kicked the bucket. You can find used 8-6-4’s with 500000+ miles still running strong. The were only around for 1 modle year on sedans and 3 on limousines because they didn’t pass the EPA’s stringent 80’s fuel standards. They were replaced with the dreaded 4100, an engine that was rushed to market with the emission failure of the 8-6-4 and did not have enough time to study the engines oil delivery system, resulting in a 20000 mile motor before failure. Given it was on the market for only a year, Cadillac used the 8-6-4 as a scapegoat.
@jacob:
That all sounds correct. Two things on the V8-6-4. First, you could easily unplug it with just one wire/plug. If you did that, then you were just running the standard 360 engine. And yes, that was one great engine. Second, many of the actual issues with the cylinder deactivation was due to faulty injectors that were shipped to Cadillac. Rumor had it (from a very good source) that GM switched suppliers mid-year. The old supplier got upset and shipped, on purpose, a large batch of bad injectors. After the certain VIN #, they had very few issues due to the new supplier.
As for the 4100 engine: Yes, it was certainly not the bright spot for Cadillac. However, I can personally attest to seeing many of them with well over 150K on the original engine. The secret was to change the oil every 3K no matter what, flush the radiator every other year (and put the pellets in the other years), and just keep a closer eye on them. More work than was expected, but if done they would run the miles.
Seriously? 150K is not a benchmark any vehicle should be judged by if made in the last 30+ years. Clearly, the solution is not 3K oil changes, it’s get rid of the vehicle once you notice that.
On the other hand, I can see an argument for the NEXT owner receiving this troublesome blob and needing to get a little life out of it, except this is requiring action not thought. Writing something easily with 100 words, is not the same thing as the burden (or expense) of doing it.
Flush the radiator every other year and use pellets too? Just no, avoid the vehicle. Even if you got one cheap used, it’s a false economy to have to babysit something that much and still ultimately have expensive repairs because you were just trying to delay the inevitable.
“Seriously? 150K is not a benchmark any vehicle should be judged by if made in the last 30+ years”
Well then, it’s fortunate that they quit selling them over 30 years ago.
I have a GMC Sierra with the 5.3 and the cylinder deactivation. Mine works seamlessly. If it weren’t for the fact that it has a Flowmaster cat back system (not loud-just some sound) I don’t think I’d even be able to tell that it is working. If I turn the radio off and listen I can hear a slight difference in the exhaust note. Also have an ATS with cylinder deactivation and if it weren’t for the light on the dash that indicates V6 or V4 I’d never even know that the car had this feature. The stop/start feature was also mentioned above. My ATS has it and thankfully it has a button on the console next to the shifter to deactivate it. Yeah, that feature is hideous. Wouldn’t have bought the car if I couldn’t shut it off.
“Future costly repairs” haha, sure. A) those lifters are still in there and being used, B) there are so few failures that is irrelevant, C) that is offset by the extra gas costs associated with having it in V8 mode the entire time and bypassing a gas saving feature. That is a red flag with the company when they state potential costly future cost savings because of failures, they have no idea about that.
Historically, you’d be wrong. This is expensive to repair, more so than the amount of fuel saved.
I get it, you are confused about all the snake oil products out there that claim to save fuel and feel this is somehow in the same vein of products when it instead solves a problem that customers did not want to have – certainly anyone who cares to, can repeat the results of others who have seem faster wear from cylinder deactivation.
It is fairly well proven to have problems. If you want to say they fixed it, then the first thing to fix it would be give existing customers new firmware that deactivates it without having to buy an aftermarket dongle to do it.
I bought and installed the Range module. I was reluctant to purchase this but it was recommended and a last resort. The AFM on my ’07 Avalanche was causing “cylinder 1 misfire” codes that then caused “Service Stabilitrak” and “Service Traction Control” codes. The truck would then “hard up-shift” at each shift. The GM “book” cited the first repair to be cam and lifter replacement. Sorry, not going to happen with 252K on the odometer. The owner of the shop pulled his Range out from his ’18 Silverado for me to try as a last resort. It was an immediate fix and runs absolutely perfect with it. Definitely pricey but i pull it from the ’07 and put it in my ’13 Avalanche when i drive that one.
Ok, take the following with a grain of salt. The last 120K miles i averaged 13.4 MPG. Since i started using this, it is now 14.1 MPG.
I agree with Dave, the AFM should be an option that can be easily disabled by the customer.
All,
I just commented on Vickster below and thought I’d provide brief update to my experience with my Range so far. I have over 9000 miles with it installed and I’m currently at 259,000+ miles and my average MPG has now dropped to 13.4 from 14.1. This is my winter Avalanche and has a lot of idle/warmup runtime but I feel my MPG is roughly the same factoring that in. I had the driver side rocker arm cover (see the technical service bulletin (TSB) on this) replaced before installing the Range. That helped reduce oil consumption from 3 quarts every 3000 miles to two quarts every 3000 miles. Once I added the Range, my oil consumption is one pint every 3000 miles. This has been consistent for three consecutive oil changes.
I’ll report back if there is any significant change.
The failures might be few to you, but for me, I had collapsed lifters twice in the last 3 months. Fortunately I’m still under warranty, but had I not been, it would have cost me $3500 every time. I need to disable DFM. It ain’t worth a couple extra MPGs if it’s gonna cost me $3500 at the repair shop every couple months.
The lifter issue on the 6.2L with fuel management tech continues onto the 2021 GM models. My brand new $85k Yukon Denali 6.2L w/ DFM just failed while on a road trip at only 7k miles – the problem? The lifters and rods. The dealer said if it wasn’t under warranty, it would be a $5,000+ repair because that type of engine needs to be nearly completely deconstructed, head gasket replaced, etc in order to access the lifters. Now the vehicle is still in the shop 5 days later. This is such a prevalent problem, lifter failure is on the radar of Lemon Law lawyers. Even the service writer told me he sees them all the time, and they have a “big” potential of recurring. So yeah, you are wrong about A) the prevalence of the problem and B) repair costs being offset by what an owner would save on gas. I figure at 7k miles, and costing $5k to repair, that’s what… 75 cents a mile in repair costs?
I have a 2021 GMC Yukon SLT $72k that at 4500 miles on a spring break trip just had lifter failure. In shop. Dealers said seeing a lot of these recently in higher volume sales areas. Crazy but an engine guy said put module and you will have a great motor.
Searched and found this thread. I need one.
I just put the Pulsar LT on my 6.2L Sierra 1500 AT4. I haven’t had any of the issues with the lifter but didn’t want to take the chance.
I have a 2021 GMC Denali Yukon xl with the larger engine. My lifters failed on a road trip with my kids around 5000 miles 4 weeks ago. It was in the shop for a week and they allegedly fixed the problem that was “just a fluke thing” that “would not happen again”. Fast forward 2 weeks later and I had my 3 small kids on a 8 hour trip for spring break and my car starts making a horrible noise again and not accelerating normally. Took it to a nearby dealership and it was the lifters again. They have now had my brand new car with less than 10k miles on it for 2 more weeks. They have no idea when they will get parts in and when it will be fixed. They will also have to ship my car to me back home, as my car is at a dealership 8 hours away. The GM corporate people have been absolutely useless! They wouldn’t even get me a rental car to get back home. The local dealership took pity on my and loaned me a car off their lot so I could get back home and they hired drivers to come pick it back up. GM corporate literally couldn’t find me a rental car for 5 days! Absurd. They said they were “trying”. I want my money back. Corporate calls me every two days to “check in” and they have NO new information. They can’t tell me when it will get fixed. They won’t tell me if they will repurchase. They just say “your case has been escalated”. This has been the worst experience. When you pay that much money for a new vehicle, you expect it to be reliable. This has been the most unreliable vehicle I’ve ever owned.
I had both an 81 and 82 Cadillac and both were engine disasters. The 1981 had nothing to do with electronic cylinder deactivation in the same way that the newer afm/dfm operate. What it did was to collapse or deactivate the valve rocker fulcrum (solenoid) on specific cylinders and those same cylinders were always deactivated when the engine was running on either 4 or 6 cylinder function, as opposed to the newer cylinder deactivation system which rotates the deactivation process of all cylinders in a rotational sequence by collapsing the hydraulic lifters allowing all cylinders to deactivate in a sequence.
The problem with the 1981 4-6-8 engine was that the specific deactivated cylinder would cool down and and consequently foul the spark plug and when the deactivated cylinder was reactivated the fouled plug would misfire and further foul that plug.
The Cadillac dealer just loved this system as it brought the customer in every 3000 to 4000 miles to have the plugs cleaned, which is what they never did, instead they installed an entire new set of spark plugs at a $120 to $130 thus generating cash flow for the dealer which was caused by a Cadillac design failure, deactivating the same cylinder each time the 4 or 6 deactivation came into play.
Hope they make enough money now to cover their R&D expenses because this is so overpriced that they won’t be able to sell it long in this internet age where people will soon have access to less expensive alternatives copied from their design.
In other words, they better be ready to mark it down to $20 price point within the next 12 months. It’s THAT overpriced.
Well the problem with this story as well as Range, is there is no mention that there DFM disabler only currently works on 8-speed transmissions. They are still beta testing the one for us with the 10-speed transmission.
I just spoke with a Range Technologies technician who advised it doesn’t matter which transmission you have with the 2019/2020 Silverado 6.2 motor.
Strange I just looked over my email string with them again to ensure what they said. ” Adam, unfortunately we do not officially support the 10-speed vehicles yet. The units we currently have will generally work for the 10-speed vehicles, but there are some links that still need to be worked out.”
So unless all the links for worked out over the last few days I would say not everyone at Range is on the same page.
Thank you for the additional information Adam.
I guess that would explain the P25a2 code I got on my new Sierra 1500 AT4 with the 6.2L and 10 speed. I guess I need to talk to Range about it and find out if they have plans to send out new units to those that bought them.
I spoke with Range, a rep by the name of Anthony on the phone. After asking him several times he advised it would I’m fact work and the kinks had been worked out for the 10-speed. Two days later after paying for the damn thing, I received an email advising “No it does not work for the 10-speed and will be some time before it’s available”. So save your time, as it appears no one is on the page over there and love wasting people’s time and money.
I just sent them a long email to make sure I cover myself for the 30 day window to return the product. I bought it last month and it did not have on the page it wouldn’t work with the 10 speed. I guess it will be shipped back and wait for either one that works to come out. Or wait till the factory warranty is out and get a full programmer for the truck.
When I got in the truck today to go to work the code was gone. I guess I will be running without the Range plugged in until they resolve the issues.
Don’t blame you, have to cover your ass. And the code being gone doesn’t surprise me since their product is plug and play without flashing the ECU in any way.
Totally sucks though, I hate this DFM. I also hate that our trucks are limited to 98MPH. Oh well is what it is I guess.
Not to brag or anything but for some reason mine is governed at 112MPH….
Thanks for your help!!!
Well sh…..Glad to know. I will be changing mine soon enough, so glad to know what they have for the AT4. I think 115 is the max I’d change mine to.
I got mine to 99 I was standing on the gas pedal!!
Looks like they finally have a product out that takes not only the DFM, but several other things like Auto Start/Stop, speed limiter, etc.
Yeah, I was looking at it a few days ago. Double the price for almost the same options as the Range device. I may end up biting the bullet and getting it.
Working perfectly on a ‘19 Silverado with the 5.3 and 8 speed transmission. Worth the price to me to actually have all cylinders firing when I make a right on red.
Yes the current model Range sells works for the 5.3 and 6.2 8 speed, but not the 10-speed. Their I’m hopes of having it soon.
Does it work with 2021 5.3L 6 speed ?
I have HP Tuners for my 2016 LT 5.3/8 spd in a Jeep. AFM is a flick of an icon and “Write Calibration” and 3 minutes to download.
Do tell us more!
Have you guy’s heard the latest? Ford will be coming out with cylinder deactivation on the 5.0 in the F150 for the 2021 model year.
I have a 2011 Silverado with 4.8 v8 runs great
It has no active fuel management
They stopped making those engines
No they haven’t!!! I have a 2017 Silverado 1500 and it most certainly has AFM!! In fact, every few hundred miles, add oil popped up…kept taking it back to dealer and kept getting the same story…so, I bought one from range and finally got almost 3500 miles until the dreaded “add oil” popped up!!! Haven’t really lost any substantial mpg.
They stopped making the non-AFM 4.8.
I have a 2021 GMC Sierra SLT Crew Cab with 4837 miles on it. It had to be towed to the dealership because the engine was making a loud tapping sound followed by a shudder. It has been determined that the lifters are bad and need to be replaced. Now I am wondering is this going to happen every 4000 miles? I am thinking about getting one of these Range products to protect my truck, my question is will it void my warranty and extended warranty?
Vickster,
Range claims that it is warranty safe it does not flash your computer and everything goes back to normal as soon as you pull it from your OBD port. I believe them since I haven’t heard of anyone having a problem.
I have a 19 Silverado 6.2 10 speed and just saw several videos on the Pulsar Lt. I will be looking into that purchase soon. This unit disables DFM, Auto Stop, allows speed limiter adjustment and several others. I purchased a programmer for my 14 Silvetado several years ago. I deactivated AFM, adjusted throttle response, transmission shift points and transmission firmness. Not sure which adjustment or if it was combination, but my mpg went up several mph to over 25 on long trips. With full v8 mode, it appeared to me the truck downshifting was a lot less, therefore saving fuel with lower rpms. Not sure if the outcome will be the same but I will try it on 6.2.
The idiocy displayed by a once great company like G.M. is just beyond belief, with their cylinder deactivation system. And they wonder why sales are down? Who in their right mind wants to spend $55,000 to purchase an anemic 6000 pound four cylinder vehicle to pull their heavy trailer or boat? And even If I wanted a four banger, I’d of bought a quality one, like a Toyota.
Check the website GM Truck. They have the announcement about the new trucks that will be equipped with AFM/DFM, but will be deactivated due to the worldwide semiconductor (chip) shortage. They did not say if they received the parts whether they would activate them at a later time or not.
Anybody try this out on a 2016 GMC Yukon Denali 6.2L? Any issues or success? Please let me know I just purchased one and I will let you know as soon as I get it to try it out. To be honest, the only thing I see with the V8 to V4 switch is the clunk from 1-2, the occasional shudder and the throttle response. Overall occasionally a rough ride.
Lenny
2016 GMC Yukon Denali
3rd time replacing lifter on cylinder 4 – costly! Has anyone had a lifter collapse after using the range? Deciding on whether to spend the 200 or trade in (if anyone would even take this since EVERYONE seems to have same issues!!!!
Hi Melody,
Your problem could potentially be different than what people here have been experiencing. If you were to add year of vehicle, engine size and some oil consumption info we could probably provide an idea if this may be a good application for the Range.
Well I just received my range technology today and installed it In my 2016 Yukon Denali without any issues. I drove it for about a half an hour up to 80mph and it seems to do what they advertise it should do. I think it is shifting smoother as well. I will give you a follow up when I have driven the truck more. Currently without the AFM disabler hooked up, I get about 20 to 25 mpg…..when I drive very easy. Mostly highway and cruise control driven. It would constantly go into 4 cylinder mode under light load. More to follow!
Lenny
2016 Yukon Denali
I’ve had my Pulsar LT installed for about 2 weeks on my 2020 6.2L 10-speed Silverado. So far all is well, corrected my tire size, disabled the DFM and the auto shutoff. The throttle response set to 5 is to much for me but 3 is perfect. Lost about 12 miles per tank so far.
I have had the Pulsar LT on my 2020 Sierra 1500 AT4 6.2L 10 speed for about a month and a half now. I have the DFM and auto start/stop turned off and have the speed limiter moved up a little bit. Overall I seem to be getting about the same MPG as before.
I also installed an oil separator between the PCV and the throttle body because I was getting a lot of oil blow back to the throttle body. After about 1000 miles, the separator already has about 1/2 to 3/4 an ounce of oil in it.