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Showing results for tags 'lifter'.
Found 8 results
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Unfortunately this is my first post here. But thought my info would be helpful to others. My new 2022 GMC Sierra 1500 AT4 Limited with the 6.2 has been in the shop for a couple days due to lifter failure. The truck had right at 6,000 miles on it when the lifter collapsed and bent a push rod. I called the dealer for an update, and they said parts should be in in the next day or two, then they'll replace the affected bank of lifters..... I asked why they won't replace both banks since the failure occurred in less than 8,000 miles? They told me that particular TSB procedure stopped at the 2021 model year. The 2022's will only have the affected bank side replaced even if failure occurs in under 8,000 miles on your brand new truck. I've opened a case with GM directly to try and get both banks replaced since the parts still seem to be substandard. I don't want to be pulling my camper with my family, and have the truck fail on me again because they only replaced half of the defective parts. I can't even get a loaner from the dealership while the truck is being fixed. Aside from this current headache, I absolutely love our new truck. No plans on getting rid of it, I just want it fixed the right way with parts that aren't inferior. Edit: The truck has a build date of 12/21. Unsure of engine build date, but have to imagine it's close to the truck's build date. -
I have what I swear to be an exhaust leak from the header or where it connects to the cat but the dealer said it's a normal sound. I don't hear it at idle but under light acceleration or deceleration, it sounds like a 20 yr old Ford work van. Anyone have a similar sound that's apparently normal for a 6.2?? I also have a loud lifter ticking/knocking noise. It happens every morning and if I let it sit long enough during the day. Thanks in advance. Here's a video of the lifter noise. https://youtu.be/t9UFIEB1TWI -
Anyone else have multiple issue regarding the lifters? I purchased a demo truck with 3900 miles on it back in early May. Started having engine issues almost immediately and had gotten all my lifters replaced recently, with under 7,000 miles on the truck. Spent almost a month at the dealer and finally got it back. They replaced all the lifters the first time and then a few weeks later it started having issues again. Luckily with the market conditions today I was able to trade out and get a newer one but I gotta admit I'm concerned. Anyone else dealing with this issue repeatedly? -
I have read hundreds of AFM collapsed lifter threads but have not been able to find someone with my same issue where it has been solved. Looking for your expertise in the cause, not looking for advise to turn AFM off as that is the plan but I want to properly fix the issue first. I have a 14 Silverado with a 5.3 with 50k miles and the issue I’m having is there is a pecking/knocking/rattle only when the truck is under light load while it is in V4 mode. Has anyone else experienced this where the noise occurs only while in V4 and while slightly accelerating? The are no check engine lights, no noises at idle, no noise while running on 8 cylinders, no smoke, no oil usage, and it doesn’t appear to have lost any power. The two possible problems I see are either: 1. One of the AFM lifters have failed in a way where it is not allowing the cylinder to deactivate which means the intake or exhaust valve will function like normal instead of closing during V4 mode. If this is the case is there any way to confirm this without a diagnostic scanner to put the truck in V4 at idle or to deactivate each cylinder? Is there any risk of further failure by not fixing this if I turn off AFM as it seems the “tabs” are just not disengaging within the lifter? 2. There is an issue somewhere within the VLOM portion with an actuator, oil port, something electronic that is preventing enough oil pressure to deactivate the lifter. If AFM is deactivated is there any risk with whatever is not working properly within this system? Basically, I am fine with turning AFM off as where I drive there is likely minimal impact but I don’t want to turn it off just to cover up a problem that will resurface in the near future as I don’t intend on getting rid of the truck any time soon.
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Thought I’d share what’s going on with my 2012 6.2L Yukon XL. Warning its long, but perhaps it will help someone with the same issues. The short & sweet: L94 6.2 AFM motor with cold start noise. Lifters were replaced prior to our purchase about 9 months ago, and this week my dealer replaced the camshaft & lifters noted camshaft damage. Videos of noise before and after below. There is still a noise after the repair, piston slap - and would you say normal? The detailed story. Purchased 9 months ago in North Alabama. 2012 Yukon XL Denali 6.2L (L94 with AFM) AWD. 1 Owner, 89,897 miles. Apparently at 89,741 (2 months prior to purchase) the lifters were replaced under powertrain warranty, no evidence the camshaft was replaced at that time. I purchased it without that information provided. But no problem, it was running smooth at the time, warm spring Alabama temps. My dad works in parts so had a friend pull the RPO codes & transaction history for the truck, thats how I found out about the lifter work. I did a clean up oil change right after purchase then swapped to my AMSOIL batch on hand. Fast forward to November 2015 timeframe. The nights are getting cooler, and I start to notice the noise at cold starts. The noise disappears once the motor warmed up, and I mean FULLY warmed up. It would clatter for 15 miles to town. I started researching and found TSB & lots of reports of lifter noise, piston slap common with these motors. I honestly wasn’t sure which it was so I laid out my plan to try and eliminate the lifter noise possibility since it was just repaired. From the start of November I completed 3 oil/filter changes. I downgraded from my AMSOIL filters and oil to ACDELCO filters and whatever Dexos oil I could get my hands on. I removed the intake manifold and did a good cleaning of the manifold and intake valves (added a nice catch can as well). I replaced the oil pressure sending unit and the little filter (it was clean but had to check). I removed the valve covers and removed each rocker, cleaned each pushrod with a pushrod brush & B12. I then sprayed a little B12 through each pushrod onto the lifters. Then poured fresh oil over the rockers to prevent dry start. All looked good internally from the get go. After the cleaning & immediate oil change the first start up sounded good! I honestly thought some contaminates just got in the lifters and the cleaning helped. In hindsight the temp was around 60 so the sound was probably just muted. The next day a cold morning, the noise was back. Now even more of a shrill at times with any acceleration. The holidays hit and delayed my trip to the dealer. So last Tuesday I dropped it off at the dealer with 97100 miles. I simply told the service lady it had a bad cold start noise with a prior history of motor work before our purchase & to please have it left outside overnight for a cold am start. The next day she called to say the mechanic has ordered a camshaft & is trying to find out from the previous dealer if the camshaft was ever replaced. Would take a week to repair under powertrain. I had him replace the oil pump & water pump while he was doing the surgery at no extra labor cost. Picked the truck up last night. The mechanic stated he could not find any evidence that the prior dealer replaced the camshaft only the lifters at 89,741. So he replaced both the camshaft & all lifters again. Stated he did find camshaft damage & not sure if it occurred before my purchase or not since it wasn't replaced. He said the motor internally looked real good for one of this millage & the pistons were rather clean (he speculated they had carbon knocked off during its last tear down). So now, the next morning, the temp is 30 outside. I start it up and it has a similar noise to what I brought it in for. It still continues to tap for a good 15 min of driving. Piston slap? I'm hoping this is just the normal noise & we can go on for another 10 years with no major tear downs. Please set my mind at ease. Thanks! -
I have a 2015 Silverado with the 5.3L that just had the number 7 lifter collapse.... Just normal acceleration and lost power. Sounds like this is a common issue with the AFM engines... I took it in to the Chevy dealer and they want way too much to replace the lifter and check the cam for wear. Of course, my warranty was done 20k ago at 160k so I'm wondering what are my best options. Does it make sense to repair and hope nothing else goes wrong or spend the money on a new or salvage engine with low km and pay to put that in?? I'd like to keep the truck for a long time if possible. What would you do in this situation?
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Hi I have a 2007 Yukon that only starts ticking when I am parked at idle for 5 to 10 min,,,starts then gets loud. Once I rev the engine or start driving it disappears....Had the whole top of motor redone 3 yrs ago by a dealer.....Broke now and wondering if maybe have someone shut off the afm could possibly stop it being it only happens when I am idling
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Hi I have a 2007 Yukon that only starts ticking when I am parked at idle for 5 to 10 min,,,starts then gets loud. Once I rev the engine or start driving it disappears....Had the whole top of motor redone 3 yrs ago by a dealer.....Broke now and wondering if maybe have someone shut off the afm could possibly stop it being it only happens when I am idling
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