Lifter/pushrod failure questions?

[Amcguy1970]

29 minutes ago, KARNUT said:

I’m older and love reasonable changes. Being a retired business owner we (family business) usually were first with changes. I was doing 25K oil changes in the 90s. We were one of the first Amsoil dealers. I’d admit I hate cylinder deactivation, too many moving parts. The bang for the buck isn’t there. I had one tested it on and off with no noticeable changes at 72 mph. Electric cars I can dig it. Mostly for the performance as a hybrid. Maybe later when they can go 500 miles on a charge, AC on, I can go full electric. Now even Ford has gone cylinder deactivation and Toyota is dropping the V-8. Times a changing. If I had to buy new I’d go turbo before cylinder deactivation. Otherwise my Avalanche is a keeper.

A ha, that is it, that explains everything, the source of all your angles and views on vehicle topics...

 

"I had one tested it on and off with no noticeable changes at 72 mph" This is just funny, so many 3rd party tests (not GM self tests like Amsoil is used to producing) have shown that to be not true. What did it show at 71 mph or 65 mph? Not sure how you got it to be the same, as an amsoil dealer I bet there are ways it can be accomplished through slight of hand manipulation. That is like the guys who say the air dam has no fuel savings yet countless third party/independent tests as well as just common sense science shows otherwise.

 

I tested one as well but at 70 mph and I showed a 1.1mpg gain, hmmm... Who is right between our tests? 

 

Tyler

Edited October 5, 2021 by Amcguy1970

[KARNUT]

6 minutes ago, Amcguy1970 said:

A ha, that is it, that explains everything, the source of all your angles and views on vehicle topics...

 

"I had one tested it on and off with no noticeable changes at 72 mph" This is just funny, so many 3rd party tests (not GM self tests like Amsoil is used to producing) have shown that to be not true. What did it show at 71 mph or 65 mph? Not sure how you got it to be the same, as an amsoil dealer I bet there are ways it can be accomplished through slight of hand manipulation. That is like the guys who say the air dam has no fuel savings yet countless third party/independent tests as well as just common sense science shows otherwise.

 

I tested one as well but at 70 mph and I showed a 1.1mpg gain, hmmm... Who is right between our tests? 

 

Tyler

Your just too funny. I’ve read test that claim little to no gain at HWY speeds. It isn’t just my experience. On many trips across country it was rarely on. Usually only down hill. Now at lower drag around 60 mph it on more often and may offer some gains. In reality it used in control environments to raise GMs mileage ratings during their testing. Some people are so gullible. But hey rock on.

[diyer2]

Hence why you still have a lot of guys doing 3k mile oil changes or even 5k mile oil changes. Tech nowadays is good enough to where you really don't need to do those things.

 

 

I'm an old guy. With the newer valve trains having more moving parts and lots of other changes on todays motors I will change my oil like I have for over 50 years. It has worked well. Cheap insurance. I'm not lazy and I can afford it. 

I respect everyone's opinion. But I don't like being told my way is the wrong way. 

 

I don't care what any manufacturer thinks/says is the proper way to maintain a vehicle. The way I have maintained vehicles has proven to me it works. That's all I need to know. 

 

 

[shakenfake]

Oh sure you can always continue to change early, never said it was the wrong way. I'm just saying you are not required. 

[Adamace1]

I have got 25mpg on a tank, 26mpg on another tank, and 27 mpg so DFM does seem to work with my 5.3 4x4 crew cab standard bed. Back when I owned a 2000 silverado the best I ever did was 21mpg. Considering my new truck is bigger in every way, has more power, I'm impressed at my mpg numbers. I idle alot at work, drive around jobsites and my average on fuelly is over 20mpg. 

 

My truck came new from the dealer overfilled with motor oil, I drained 3/4 of a quart out. I wonder how much over filled it has to be to start making the motor oil foam up causing a lifter problem? It's hard to tell how much overfilled it is with these new dipsticks. I like the old blade type where you could tell where the oil level was, these new ones make it where you can't tell if oil is on the cable part when it's overfilled.

Edited October 6, 2021 by Adamace1

[Grumpy Bear]

1 hour ago, Adamace1 said:

I have got 25mpg on a tank, 26mpg on another tank, and 27 mpg so DFM does seem to work

 

Dad has a 1998 RCLB 4.3 and says he gets high teens to low twenties with it. I have a 2015 RCSB 4.3 with a lifetime hand calculated average of 28 mpg over 150K miles. AFM/DFM works and maintaining it?....well..... Change your oil, drive like a WISE adult.

 

 

If the current 4.3 were available in a truck the size of an S10 or S15? 300 hp in a lightweight truck getting 40 mpg +???? That would be some fun, right? More fun than we are ALLOWED to have. 

 

 

Hint. Guys that say it doesn't work are guys who drive fast enough to never or seldom have it engaged. It is a LOAD based system. 

 

Look we live in a time where government has got the OEM's by the short and curly. They have the oil companies in the same bind and the looser is the consumer. OEM's are engineering with less and less safety factor, Oil's are reverting to pre 1940's levels of anti-wear and detergency. A perfect storm for disaster. Well and a time were 'Greed" is the normal and no one gives a crap about 'right'. 

 

The deck is stacked against you so stop playing by the cheaters rules! 

 

 

 

[Grumpy Bear]

8 hours ago, Amcguy1970 said:

A ha, that is it, that explains everything, the source of all your angles and views on vehicle topics...

 

"I had one tested it on and off with no noticeable changes at 72 mph" This is just funny, so many 3rd party tests (not GM self tests like Amsoil is used to producing) have shown that to be not true. What did it show at 71 mph or 65 mph? Not sure how you got it to be the same, as an amsoil dealer I bet there are ways it can be accomplished through slight of hand manipulation. That is like the guys who say the air dam has no fuel savings yet countless third party/independent tests as well as just common sense science shows otherwise.

 

I tested one as well but at 70 mph and I showed a 1.1mpg gain, hmmm... Who is right between our tests? 

 

Tyler

DING DING DING

We have a winner

Fact!

Run 100 mph and there is no difference

Fact! 

Run 55 OR LESS and there is a huge difference

Disciple is not a "common"  human mode of operation

Is it?

 

OEM's nor the government can rule, engineer nor mandate a system that some self-entitled "Me First" personality can not circumvent. 28 States or US territories have maximum two lane speed limit of 55 mph OR LESS. People who believe they have a constitutional RIGHT to disregard public safety and law will not benefit from it. BTY...you don't. 

 

 

[KARNUT]

WOW news flash boys and girls. If you drive under the posted HWY speeds you get better fuel mileage. And I agree. My GPS alerted me to a two lane in South Carolina because of an accident. 60 mph was the speed limit. My fuel mileage went up. DUH. I don’t believe anyone cruises at 100 mph. When it’s noted that cylinder deactivation isn’t much good at Hwy speeds. It’s the posted speed limit. If people want to stick to secondary roads for better fuel mileage I’m cool with it. 

[Kilgore Trout]

On 10/2/2021 at 9:14 AM, Adamace1 said:

I'm wondering if there is any common maintenance between the people who have lifter/pushrod failure.

 

1. Did any of you owners who had failures do your own oil change? As in you know what oil/ filter was put in, and you know it was at proper level. Or is it serviced away from you so you don't know what oil is put In it?

 

2. When did you change your oil? How many miles on oil? What percent of oil life was left?

3. Do you idle alot?

 

I change my own oil mobile one 0w20. Ac delco pf63e filter. 

 

I change at below 5,000 miles usually 30 to 40 percent left on oil monitor. No engine problems yet. 2021 with 24k miles

 

I do idle a couple hours a day with my truck.

 

I just bought a 2021 Sierra 6.2L.  I will be changing my own oil.  I had a long talk with the service advisor I have known at my local dealer for a very long time.  I asked him about the lifter issues on these late model engines and he confirmed it is real and a problem.  

 

I own a 2007 Yukon 5.3L that I bought new, am well into six figures mileage wise,  I have changed my own oil most times at 5K intervals, Valvoline Full Synthetic 5W30 and WIX filters.  When I didn't change it myself, I had it changed at my dealer.  I have never had an AFM lifter fail, but I did tune out AFM recently, just in case.

 

Getting back to newer DFM design and problems, the service advisor stated that they have had a number of customer trucks that needed new lifters.  He said almost all the failures of 2021 model year trucks had initial failures before 8K miles.  He maintains one company's fleet vehicles and he said they had extremely high failure rates (like half) and they were all early examples of the 2021 MY.  He said early on they replaced just the failed lifters or a single bank, and everything else looked OK, so put the truck back into service.  Of the units they changed one or just one bank of lifters they had an alarming return rate for the same lifter failure issue.  He indicated these second time failures almost all happened within the 20K total mileage on the engine window.  What I failed to ask him was if the return failures were with lifters that were not changed the first go round (a key fact that would tell us a lot about the source of the problem).  He went on to say that they have since made it policy to change all 16 when any lifter failure happens on these late model trucks.  He stated if I had a failure of any lifter, they would be changing all 16.  

 

I also didn't ask him if his fleet customer that had a high failure rate, if the trucks were acquired during the "bad lifter window" identified by GM, but given it was late 2020, early 2021 is when they bought the trucks, my assumption (at least until I see him again and remember to ask him) is these fleet trucks were produced in the "bad lifter" window.

 

My truck was made in October, so I have my fingers crossed the faulty lifters have been purged from the system.  

 

When I asked the advisor if he would do anything special with regard to maintenance, if it was his truck, and he said he would definitely change the oil and filter at 1500 miles, again at 3K miles and then every 5K miles from that point on.  He said he would never run one of the AFM/DFM lifter equipped engines to the recommended 7.5K interval.  The 1500 and 3000 changes will be a change to my original plan, but the 5K interval is normal for me, so nothing new.

 

I am investigating whether a tune out of the DFM is possible in my PCM.  It was a very simple change to my 2007 Yukon SW. I will probably contact a few of the tuners I know who do good work and see if they have cracked the 2021 SW code and can turn the cylinder deactivation off in my new ride.  If they can, I will almost certainly do it.

Edited November 6, 2021 by Kilgore Trout

[Mars Denali]

On 10/2/2021 at 8:14 AM, Adamace1 said:

I'm wondering if there is any common maintenance between the people who have lifter/pushrod failure.

 

1. Did any of you owners who had failures do your own oil change? As in you know what oil/ filter was put in, and you know it was at proper level. Or is it serviced away from you so you don't know what oil is put In it?

 

2. When did you change your oil? How many miles on oil? What percent of oil life was left?

3. Do you idle alot?

 

I change my own oil mobile one 0w20. Ac delco pf63e filter. 

 

I change at below 5,000 miles usually 30 to 40 percent left on oil monitor. No engine problems yet. 2021 with 24k miles

 

I do idle a couple hours a day with my truck.

 

[Mars Denali]

Just now, Mars Denali said:

 

Well after they bought back my 2015 Yukon Denali at 80,000 miles I went ahead and bought a new 2021 Denali with that PIA 6.2 L engine ! It’s had two engine failures during the first 8k miles and lucky me it just happened again at 9300 miles. They keep saying it’s valve guide failure but after research and being told by my GMC service  dept it is Rod failure caused by the cylinder deactivation system and it’s going to keep happening until they address it and change the rod design. Anyone else having  this nightmare ?

thanks Steve 

[Kilgore Trout]

7 hours ago, Mars Denali said:

Well after they bought back my 2015 Yukon Denali at 80,000 miles I went ahead and bought a new 2021 Denali with that PIA 6.2 L engine ! It’s had two engine failures during the first 8k miles and lucky me it just happened again at 9300 miles. They keep saying it’s valve guide failure but after research and being told by my GMC service  dept it is Rod failure caused by the cylinder deactivation system and it’s going to keep happening until they address it and change the rod design. Anyone else having  this nightmare ?

thanks Steve 

You might want to get a second opinion.  I can't imagine a rod failure because of anything with DFM.

[Adamace1]

Well I get to answer my own question. I do all my own maintenance, change oil early. Still had lifter fail on Monday of this week at about 28,000 miles. Truck was built during bad lifter window TSB. 

Edited November 18, 2021 by Adamace1

[Grumpy Bear]

3 hours ago, Adamace1 said:

Well I get to answer my own question. I do all my own maintenance, change oil early. Still had lifter fail on Monday of this week at about 28,000 miles. Truck was built during bad lifter window TSB. 

 

So you have a truck with a known bad parts and are amazed that religious service didn't save it? 

[KARNUT]

So the king of early OCIs to save a bad design. Who has multiple threads about it. Is chastising a person who is doing early OCIs to save a bad design. It’s early I had to read it several times to believe what I read.