Lifter Issues?

Just bought a ZR2. Have 8000 miles on it. Driven across country 3500 mile trip. Zero problems. Did have to replace a bad fuel injector. As far as lifter problems. I have owned 2 trucks with 5.3 and a Camaro with 6.2. Have had zero problems with lifters. I changed my oil after the first 1000 miles. Change every 4000 miles. I know a few guys who also add some transmission fluid right before changing the oil. Great detergent. What I have been told, the small holes the move oil to the lifters can get clogged. Results in poor lubrication equals lifter failure. Also use a good Ester base oil. I also run super unleaded, obviously better gas mileage. Also recommended. Just my 2 cents.
 
Just bought a ZR2. Have 8000 miles on it. Driven across country 3500 mile trip. Zero problems. Did have to replace a bad fuel injector. As far as lifter problems. I have owned 2 trucks with 5.3 and a Camaro with 6.2. Have had zero problems with lifters. I changed my oil after the first 1000 miles. Change every 4000 miles. I know a few guys who also add some transmission fluid right before changing the oil. Great detergent. What I have been told, the small holes the move oil to the lifters can get clogged. Results in poor lubrication equals lifter failure. Also use a good Ester base oil. I also run super unleaded, obviously better gas mileage. Also recommended. Just my 2 cents.
I agree. Those lifters are strange looking compared to regular lifters ,and the holes are tiny.
 
Understood...with all due respect, I'm not looking for someone to point out what I already read in a thread...I am looking for someone that may have an answer versus speculation. I read numerous articles (>5) late last night on-line after Google searching from several mechanics, and another from GM, that stated this was caused by AFM/DFM, in addition to what they felt was a bad batch of lifters from 2019 - 2021 and nothing more. Was hoping we had someone close to the subject on the forum that could shed additional light on 2022 and 2023 model year. We all know it's happening to the 2022's...has anyone with a 2023 had a failure of this type yet? I'm not in this for the debate either...just looking for additional "facts" and not conjecture.
All good here my dude, just pointing out it’s something that gets mentioned and examples can be found on various forums that contradict the AFM/DFM delete being a 100% solution. I am by not means saying it doesn’t help, been driving in L9 in the very hope it is the silver bullet here but I don’t think it’s a guarantee based on other examples. It’s a topic often on repeat and I’ve come to the conclusion, if I continue to own this truck, it’s simply a risk.

I don’t like it but my LML duramax was a high risk of the dreaded Bosch cp4 injector pump failure…google that, it’s a freaking nightmare. I ultimately did a cp3 pump conversion to ease my mind…others like my ol man, beat the snot out of his truck on the farm, ran it way heavy and way hard pulling cattle, equipment, and round bales. He NEVER used any diesel additives, fueled up at whatever station was in his line of sight, changed oil when he got tired of it singing at him, and had zero issues through 180k miles…go figure.

I digress, you can find examples but agree we are operating on a certain threshold of speculation. Unfortunately, I don’t think any of us have a definitive solution or mitigation option at this point in time or that would be the response on repeat when brought up. I agree with many guys here that proactive and quality maintenance is key as well (it’s just cheap insurance across the board but even that’s not a guarantee you won’t have mechanical issues)…but I would bet a good steak dinner there are guys all over the country that don’t do that either and haven’t hit the unlucky jackpot (I say that because most of us probably have those buddies, like my dad above, that you just shake your head at but somehow they just keep dodging major mechanical issue bullets by defying the car gods 😅)

I sure hope it’s something they resolve for good as it’s just ridiculous at this point we continue to even be having this discussion and pointing to examples numerous years later. I’ve read nothing that changed in ‘23 year that would lead me to believe the risk has been mitigated either.

Best of luck, for what it’s worth, I do really enjoy this truck and have 7700 miles on a ‘22 and am keeping it despite the risk at this point as it’s a solid option for what I do.
 
All good here my dude, just pointing out it’s something that gets mentioned and examples can be found on various forums that contradict the AFM/DFM delete being a 100% solution. I am by not means saying it doesn’t help, been driving in L9 in the very hope it is the silver bullet here but I don’t think it’s a guarantee based on other examples. It’s a topic often on repeat and I’ve come to the conclusion, if I continue to own this truck, it’s simply a risk.

I don’t like it but my LML duramax was a high risk of the dreaded Bosch cp4 injector pump failure…google that, it’s a freaking nightmare. I ultimately did a cp3 pump conversion to ease my mind…others like my ol man, beat the snot out of his truck on the farm, ran it way heavy and way hard pulling cattle, equipment, and round bales. He NEVER used any diesel additives, fueled up at whatever station was in his line of sight, changed oil when he got tired of it singing at him, and had zero issues through 180k miles…go figure.

I digress, you can find examples but agree we are operating on a certain threshold of speculation. Unfortunately, I don’t think any of us have a definitive solution or mitigation option at this point in time or that would be the response on repeat when brought up. I agree with many guys here that proactive and quality maintenance is key as well (it’s just cheap insurance across the board but even that’s not a guarantee you won’t have mechanical issues)…but I would bet a good steak dinner there are guys all over the country that don’t do that either and haven’t hit the unlucky jackpot (I say that because most of us probably have those buddies, like my dad above, that you just shake your head at but somehow they just keep dodging major mechanical issue bullets by defying the car gods 😅)

I sure hope it’s something they resolve for good as it’s just ridiculous at this point we continue to even be having this discussion and pointing to examples numerous years later. I’ve read nothing that changed in ‘23 year that would lead me to believe the risk has been mitigated either.

Best of luck, for what it’s worth, I do really enjoy this truck and have 7700 miles on a ‘22 and am keeping it despite the risk at this point as it’s a solid option for what I do.
I really like my truck too and I have sunk about $3500 in "accessories" into it (see my signature) and planning more like a BAK X4S tonneau cover that I had on my last truck and loved it. I could sell my truck today for a TON more than I paid for it, and it has crossed my mind. However, I LOVE the look of it...the ride...and it's capabilities, so I am going to take my chances since I only put about 6K miles a year on a vehicle and, typically trade them in every 1-2 years. If I do have an issue, I'll get it fixed and then possibly dump it and look at anything other than a Ford...but a Raptor could sway me ;) Never had a minutes issue with my 2019 or 2021 RAM Limited 4X4 and a TRX has crossed my mind too. We'll see...really hoping this turns out well for us all that have yet to have any issues develop.
 
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Michigan Motorsports has an L87 AFM delete kit but you also have to deactivate it in your ECU, which for the newer vehicles is harder and harder to do. For me, when I went through the heads on my MY12 Corvette Z06 with LS7, I ditched the LS7 lifters and went with Johnson 2110 lifters that GM uses in their COPO Camaro 427's. I had an L86 in a MY17 Denali 4x4 and never had any issues with it for the low 30k some miles that I had on it before I sold it. I recently sold my mint MY16 Corvette Z06 with the LT4 so I could buy a C8, and I was really disappointed GM stuck AFM on a 650hp Corvette where gas mileage was a zero factor when deciding upon the vehicle. I only have a little over 1k miles in my C8 thus far but I don't expect any issues with it.

If I ever had to take the heads off my new L87 in my ZR2 I'd be awfully tempted to want to do some of the same that I did to my C6Z, and add Johnson 2110 lifters with some hardened pushrods, assuming I could get HPtuners or someone to work with the ECU. Of course, then you potentially go down the major scope creep path while you're in there and the next thing you know, you're porting and polishing your heads, adding stronger valve springs, looking at new camshaft grinds, maybe an LT2 intake manifold, (or even an LT4 or Magnuson supercharger,) etc.
 
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Michigan Motorsports has an L87 AFM delete kit but you also have to deactivate it in your ECU, which for the newer vehicles is harder and harder to do. For me, when I went through the heads on my MY12 Corvette Z06 with LS7, I ditched the LS7 lifters Johnson 2110 lifters that GM uses in their COPO Camaro 427's. I had an L86 in a MY17 Denali 4x4 and never had any issues with it. I recently sold my mint MY16 Corvette Z06 with LT4 so I could buy a C8, and was really disappointed GM stuck AFM on a 650hp Corvette where gas mileage was never a factor when deciding upon the vehicle. Only a little over 1k miles in my C8 thus far but I don't expect any issues with it.

If I ever had to take the heads off my new L87 in my ZR2 I'd be awfully tempted to want to some of the same that I did to my C6Z, an add Johnson 2110 lifters with some hardened pushrods, assuming I could get HPtuners or someone to work with the ECU. Of course, then you potentially go down the major scope creep path while you're in there and the next thing you know, you're porting and polishing your heads, adding stronger valve springs, looking at new camshaft grinds, maybe an LT2 intake manifold, (or even an LT4 or Magnuson supercharger,) etc.
I tend to agree. It’s been my experience, once you crack that seal, it’s way too tempting to keep going down the path of chasing power, which requires more reliable parts, which then just asks for more…and the vicious cycle continues 😅
 
I tend to agree. It’s been my experience, once you crack that seal, it’s way too tempting to keep going down the path of chasing power, which requires more reliable parts, which then just asks for more…and the vicious cycle continues 😅
And that was the point I was trying to make, and why I ended up going with the 6.2L again. I really wanted the new LZ0 Duramax and was just waiting a few days for an AT4 LZ0 to be driven up from the rail yard in San Antonio. With the L87 there is nothing on the motor that I am not well familiar with, and there are tons of aftermarket tuning parts available (an entire industry of LS/LT parts and tuners), that for me, once I compared the ZR2 to the AT4 Duramax for about the same coin, I felt okay going with the 6.2L again and paying a little more at the pump (thank you Costco premium!)
 
Can someone who truly knows the answer to this question please provide it? Why does everyone say to run in "L9" to disable DFM versus "L10"? Is there a reason why "L10" wouldn't do the same as "L9"? The manual states that DFM will only kick in in "DRIVE"...so, if in "L", then it shouldn't kick in from 1-10...right? Thanks!
 
Can someone who truly knows the answer to this question please provide it? Why does everyone say to run in "L9" to disable DFM versus "L10"? Is there a reason why "L10" wouldn't do the same as "L9"? The manual states that DFM will only kick in in "DRIVE"...so, if in "L", then it shouldn't kick in from 1-10...right? Thanks!
I don't know the technical reason why L10 doesn't disable it. All I know is when I have ran it in L10, I can hear the DFM working when I slow down to a stop. The Borla exhaust make this obvious. When I have it in L9 the sound of all 8 cylinders kicking back in is gone, because they were never disabled.
 
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I don't know the technical reason why L10 doesn't disable it. All I know is when I have ran it in L10, I can hear the DFM working when I slow down to a stop. The Borla exhaust make this obvious. When I have it in L9 the sound of all 8 cylinders kicking back in is gone, because they were never disabled.
Thanks Diesel! Strange I think since GM says if not in "D", DFM will not kick-in at all :unsure: I guess I'll keep driving in L9..........
 
Thanks Diesel! Strange I think since GM says if not in "D", DFM will not kick-in at all :unsure: I guess I'll keep driving in L9..........
I’m going to assume the GM documentation teams aren’t looking through the lens of “how can we help guys get around the DFM/AFM?” 😅
 
Yesterday I drove in L10 for a bit. I did not notice the lifters kicking in? I have the "S" type Borla. I may not have driven far enough too see this happen. I got up to 70MPH. The difference in the two overdrives, 9 & 10, are pretty minor, like 200 RPM. I think the ratios are ,.69 & .65? Barely noticeable. I'll have to try it again when I get on an interstate. The exhaust is really mellow going down the road.
 
So no issues driving in L9? I haven’t driven a Zr2 long enough (only test drive) to find out. How do you even shift to that gear? Put in D then what?
 
So no issues driving in L9? I haven’t driven a Zr2 long enough (only test drive) to find out. How do you even shift to that gear? Put in D then what?
Pull the gear shift down again after in “D” and it shifts to “L” which is essentially a “manual” option. Then use the steering wheel paddle shifter to shift up to “L9”. You will see it on the display, then drive like normal and the truck will shift up to 9th and everything in between but won’t let it bump up into 10th

I’ve had zero issues to date
 
Pull the gear shift down again after in “D” and it shifts to “L” which is essentially a “manual” option. Then use the steering wheel paddle shifter to shift up to “L9”. You will see it on the display, then drive like normal and the truck will shift up to 9th and everything in between but won’t let it bump up into 10th

I’ve had zero issues to date
Thank you. And we know there are no issues with that?
 
in full transparency, we're on an internet forum so take what I'm saying for what it is, i'm not a GM engineer so "know" is relative... 😅

I have a 2022 ZR2 that I've got 8,000 miles on and have been running in L9 for the last couple thousand miles without any known issues. Ultimately, GM provided a "manual" shift capability here so generally speaking it's fine to run them this way. By holding it in L9, you're just not allowing it to shift into the 10th gear which does mean at highway speeds you'll run at a slightly higher RPM (i believe someone said about 200RPM's based on their personal experience testing this out). It's a feature in these trucks so it should be fine...but as I've also previously eluded in this thread, nothing is an absolute guarantee with mechanical things.
 
in full transparency, we're on an internet forum so take what I'm saying for what it is, i'm not a GM engineer so "know" is relative... 😅

(i believe someone said about 200RPM's based on their personal experience testing this out). It's a feature in these trucks so it should be fine...but as I've also previously eluded in this thread, nothing is an absolute guarantee with mechanical things.
Totally agree with what you stated above. Yes, it is fine running in L9...it will just use slightly more fuel. It does run at higher RPMs in L9 because you're not running in 10th gear which would drop the RPMs. No, there is no guarantee that this will absolve you of the lifter issues as people running in L9 exclusively have still had lifter issues 😞 Therefore, when a DFM disabler does come out from Pulsar or Range, that does not mean our problems are solved since the lifters are crap and GM is doing nothing to solve the problem. I am starting to think that we should just "drive it like you stole it" because what ever will happen will happen and nothing you can do will truly help the situation if your engine decides you're a victim.
 

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