I have read synthetic isnt good for AFM lifters. How stupid do you have to be to whine like a welfare check cashing idiot when there are literally 3 or 4 different ways to totally disable AFM. . Replaced all 16 lifters due to collapsed lifter on CYl #4. So now at 168 thousand miles it still runs good but gets bad gass mileage. I drive the same 320 mile trip every two weeks and drive the same route and full tank. There has been a lifter noise since I bought the truck 1 year ago. 1. I know I felt the same way. Can they be faulty? On June 4th you stated The vehicles affected were 2007 to Feb. 2011 AFM equipped engines (Aluminum or Iron block-L94, LZ1, L99, LC9, LH6, L76, LFA, LMG, and LY5) I am looking at purchasing a 2012 Tahoe with the LMG per the build sheet. GM tried this on cadillacs about 20 years ago and if memory serves me correctly it was a disaster. Replaced the engine with remanufactured one and had the AFM turned off with a computer hooked to the ECU. I have the towing package on my 13 Tahoe LTZ. AFM Sucks!!! Now I learn about the cylinder deactivation issue and suggestions to add the Range Technology module to deactivate it. Stopped at nearest gas station and found I was a quart low on oiladded oil and lights eventually went off and luckily we made it the 5 hour drive home. Loved the looks and interior and thought a I got a great deal at $6k even. Most will want to get rid of the AFM immediately and VVT isnt for []. They have plastic casing, so you can imagine what will happen with aged plastic. thx Brian, Knock on wood I drive a 2011 silverado 44 Ltd with the 5.3 AFM/DOD not tuned out or delete being used and have experienced no problems or any sign of problems for that matter juat rolled over 210,000 all original factory parts would you suggest I tune it out or juat let it ride I change my oil religiously and also use lucas products for all aspects of my motor. Does the disabler prevent the engine damage in the first place? There are so many more oil passages on engines these days. NOTE:If you were in a situation where youve installed the AFM delete kit, but dont have access to a programmera disabler can still be a viable option. For fun, he runs his 427-powered C5 Z06 in ECTA land-speed racing, at OPTIMA street car events, and at a mix of autocross, drag racing, and track days. I have 1999 Silverado with out AFM that gets 21 mpg and a 2008 with it that gets 14.6. They are taller and have special oil holes. Just shut AFM off. [] they have a downside? Cylinders two, three, and eight are all similar in cylinder deactivation. There is no way cylinder deactivation and the resulting temperate decrease, with sudden piston heat expansion when all cylinders are engaged, can't have undo wear and tear on the rings, valves, piston and bore. Dale, I have a 08 Tahoe thats doing the same thing.Any info you have on this would be appreciated, [] Do they have a downside? Thats not all bad because it saves the cost of an AFM delete kit. Took it to my dads and he tore things apart and found that I had a lifter that was stuck. I would rather stay a V8 full time than deal with AFM issues in the future. The lifter seems to recharge whenever the truck sits for some time. Our patented technology is the only product that will disable Active or Dynamic Fuel Management without reprogramming the factory ECU. We need availability of a replacement engine without the AFM. Ever since that which was Feb/March 2020 i get a intermittent rattle does not do it all the time and I am not getting any codes i.e. As it turned out one of the cam bearings was failing and causing the cam to wobble (my guess) which messed up the AFM and probably some other stuff too. The motor I pulled was a 2007 LY5 with about 77k on it. Ive only put a straight pipe exhaust, intake, and a boost controller on it. No other V-8 truck of similar weight can do that (except another GM with AFM). Dave, I also have a 2008 LTZ avalanche with 106,000 I have the exact same symptoms at this point I just want to sell it will the disabler help remove the check engine light wont pass inspection with light on thanks for your help Chris. Brian, I repaired a 2012 GMC Yukon Denali as the AFM lifter on #4 I take failed. The computers had not evolved enough to control the sytem. I sold them when they were new. Was thinking maybe I could trick the ruck into thinking the engine was not warmed up, however, this might cause some problems for other processes, such as mix ratio and timing. Dod is the biggest failure sence the 8-6-4 caddie in 1981. I have a 2012 Chevy Avalanche. Cant believe they havent fixed this in a decade. Once the failure has occurred, the AFM shut off methods other than that probably wont work. It works . Yes, always change all the lifters at once. More information can be found in the GM TSB bulletin number 10-06-01-008g. Because I want to. However, the fuel savings are not always as much as expected. No problems with any to this point. Correct me if Im wrong- If such an item was available couldnt you then just replace the lifters in the 4 AFM cylinders and then just run a disabler or have your ECM/PCM reprogrammed to have AFM disabled permanently. I have a 07 Yukon with 180K and no issues what so ever. Their tech guys have seen it all and may have some thoughts on this as well. Absolutely agree, but we all know GM cant afford to recall them all & definitely wont, gettin a Toyota, but first will go to GM dealer and ask to see a truck without AFM & when they say they dont have it Ill say See ya, I have an appointment with the Toyota dealer! Always had GMs never anything else till now. Its not GMs choice to use AFM. Told her that it would not last and that she needed to find a different way to get around. Who knew? The most common issue GM vehicle owners with AFM report is increased fuel consumption. Todays computers are faster so it does work. This really sucks. Our 2013 yukon with 47k miles just failed. I did noticed the oil consumption but it was rare that I would have to add oil. What the biggest reported problem with Chevy Silverados? Do you think I can still disable AFM? Seems my oil pressure sensor is bad, are showing the same oil pressure at all times, even when it dosnt run.Dont know it that fault was there before i replaced the lifters. My ignition lock cylinder is completely stuck in lock position with the steering wheel locked as well. Chris, when you did your delete, did you also change the cam at the same time? The car runs great apart from the shuddering at those speeds. Thanks for the advice Brian! All ready done valve job . There are so many moving components in an engine these days as opposed to the past. Send response to [email protected]. How did your turn out? It has the orings in place, that seals the towers. I have an 07 Yukon with over 180K. AFMengines use special lifters for cylinders 1, 4, 6, and 7. We had one for a company car in 82 and it never did run right from new but at least it didnt destroy itself. My daughters car had about 230,000 miles when she complained of the problem. IMHO . Next day, fired it up to take the the junk yard and it ran great. There are a few potential causes for Chevy cylinder deactivation problems, including oil consumption problems, harmful to the environment, sludge issues, and lower cylinder temperatures. [] swaps come with an extra step or two thanks to the Generals fuel efficiency efforts (VVT and AFM). I read something the other day which I found to be funny. [], I have 2007 5.3 its a new motor this truck scares me 9000.00 these trucks are jokes The cost of just rings $4,000.00, [] Disable your Chevy AFM: https://www.onallcylinders.com/2017/11/30/how-to-delete-or-disable-active-fuel-management-afm-on-gm-… [], [] like front timing cover, knock sensor location, cylinder head style (cathedral ports), AFM (Active Fuel Management), and other components are key clues to which engine family youre looking []. Truck ran fine before that. yep, you are 100% Right, I called a local saab shop and they filled me in, in 2005 the trailblazer and clones have DOD (displacement on demand), My next issue is getting extra ignition keys on the cheap. thanks brian love the info Im thinking of buying a ford now, I am going to buy a new truck in about a month it would be a Chevy but Dodge has lifter problems so they are out and Chevy has DoD problem.If they come out with Silverado without the DoD then i would buy one.But they arent so i will become a Ford man from now on, Have fun with that Ecobust motor & stretched timing chain . This should be added to your earlier model if you experience oil consumption. And consider using a higher grade of engine oil like Mobil 1 or Amsoil, etc. Does the Pressure relief vavle ever go bad?? I remember those Other GM vehicles that the consumer tested for GM and paid GM for the honor. if GM wont make a dependable truck for 60,000 Toyota is sure to take over even with very poor gas mileage . The Jury is still out on the Gen. 5s but the warranty could be an issue. I will be installing the AFM deactivator tonight when I get hoe. It is also known as Displacement on Demand (DoD) or cylinder deactivation. Install ls3 valley cover. a little burning oil is a minor thing, my main concern is avoiding a multi-thousand dollar repair needed to the motor. Love the truck. In four-cylinder mode, they act like air springs and allow for smooth operation. After reading these forums Im a little concerned about my decision to stay with GM. My point is that the engine likely on uses dod a small percentage of the time so can not really imagine that the delete causes any more issue than normal which may be the high oil consumption but do all of these engines with dod consume a lot of oil? It seems this tough engine has everything incorporated into it. Cost about $250, but it is not fool proof. Im looking at the Range Disabler but want to make sure it is required/suggested/recommended/safe? According to some experts, switching to cylinder deactivation reduces the emissions high somewhere between 4 and 10%, which is a huge percentage of saving the air from pollution. Your 1981 caddy was your fmu I got glue inside of it and it stuck the potentiometer for stochiometric if you get a new fmu or you pick the glue out of the potentiometer you can set it to stoichiometric and get a lot better fuel mileage as far as your truck why dont you look at the intake manifold I got a crack or a vacuum leak somewhere for gas mileage thank you truck service, Near 1981 its your fmu it has glue inside the potentiometer you have to either RNR it for a new one or pick the glue out of the potentiometer for stochial magic is the only variable resistor inside that you can turn with a screwdriver once you get the glue out of it itll read still kill metric just be careful and then you can set it properly with your own meter on your monitoring your O2 sensor and then on your Silverado thingy your 5.3 just check the intake manifold for lakes Ill get you a better gas mileage if you dont have any intake cuz theyre plastic and they crack and stuff like that other than that yeah thats it, Larry Jenkins, I have a 17 GMC Sierra 6.2 SLT, I got 25 to 27mpg regularly with 93 gas and cylinder deactivation. Jasper makes aGM engine that deletes AFM & will warranty the engine to a 100,000 miles parts & labor . There are two ways to disable or delete Active Fuel Management on your GM or Chevy Gen IV LS or LS-based Vortec engineone is to install an AFM Disabler, and the second is to install an AFM Delete Kit. Its ribbed with solenoids on the underside. Now it appears GM and their handlers want to push the electric market with throw away junk that is mechanically weak . She drove it for another 35,000 and it went out again. .or something similar . As GM issued 13 updatesnone of which workeddealers disabled the system on their customers' cars, leaving them permanently in V-8 mode. A lot more info with the ongoing GM 5.3l AFM engine issues on Cargurus. I only had 81k on the motor. The most common are fuel pump failure, transfer case sensor failure, fuel injector failure, and carbon build-up. Since no air can get in or out, four cylinders provide no power. You can monitor the oil level on your dipstick for 3,000 miles to determine if the deflector or plug would be needed, but chances are you wont based on the TSB. We did take it apart to check for metal possibly being trapped inside, it looked like brand new. I would. I asume low oil pressure cant make some of the DOD lifters to malfunction? I would appreciate any feedback. TheAFMsystem can be identified by its components. Replaced all lifters. I still get a P0336 code every once in a while but still good to drive around town. Delete the AFM, buy a tuner/chip, take it to a performance place and get an actual tune done that fixes it, replace the AFM lifters with non AFM type, change other engine components with thisetc..etc..etc??? When cruising on the freeway (for example) in 4 cylinder mode and jumping on the throttle to pass or get out in the fast lane, there is CONSIDERABLE and annoying and dangerous lag, like 3 seconds, and this is a problem. A lot of drivers reported losing 2-4 quarts of oil in between oil changes. I wear hearing aids, but I thought I heard more engine noises, but after checking the gas cap, the light went out for a week. 2015 SILVERADO 1500 44 crew cab with 5.3L engine: So two weeks ago with approx 70K miles, I had an odd noise when accelerating and then engine light flashing and riding rough. The tune is the best bang for the buck outside a cam swap anyway and what Id recommend. Pulled the inntake and replaced valleypan With all the solenoids. The oil pump is high volume, but there are a lot of people that dont change it and rely on the pressure valve to keep the volume manageable. I always have done my oil changes on time, not sure about the people who owned it before me though. Active Fuel Management (AFM) is a trademarked General Motors technology that improves gas mileage by shutting down half of the cylinders under light-load conditions to reduce fuel consumption. is it still working good since you have done that with the trans fluid? AFMis good for gas mileage and can be 5-7 percent more fuel-efficient under certain conditions. I just took a long trip and it used 1.5 quarts of oil. The biggest difference between the Vortec engines that used to be found in Chevy and GMC vehicles and the EcoTec engines found in them now are the fueling methods. Given that, would you recommend buying one of the OBD-II devices to disable AFM? Disable the afm. A tuner can often fix that as well by giving it some more ignition advance in these regions. Run it and let it soak overnight. The LH6 in 2005-06 was a little different than the one used in 2007-09, but both had AFM. This is my project car and will be my drive (about 5000 miles a year). There is a good chance that some of the drivers side lifters decided to go. Given maximum engine power is not required during the majority of everyday driving, AFM works to deactivate engine cylinders when they are not needed, such as when cruising on the highway, thus. Thankfull for any ideeas! Battery was unplugged for a week.. Service manager said nothing else needs to be replaced because the engine has a Teflon coating. WATCH THIS VIDEO https://youtu.be/1MJMf3nnQhQ. Unfortunately, I found out about the lifters too late. I guess what Im really trying to ask is,, are there any cons/disadvantages to installing the AFM delete Electronic module? This lowers the cost of building it [], [] aluminum block engine. He unstuck it and I took it for a drive and same thing happened. Any problems to watch out for?Did you replace the VLOM? Your email address will not be published. Remembered that after I bought my Tahoe. i just bought a 2018 Silverado with the 5.3 Why this happens is a more . Had nothing but trouble out of it. The secondary pressure relief in the back of the pan began to open at 55 psi and was completely open by 75 psi.