Welp…. Ya Fix One Thing…..Dreaded Lifter Tick

[17 Yukon Denali]

Ok. So driving to Fl. All seems to be running wells. I can see a noticeable improvement in MPG. Averaging between 21-23 chilling at 75 mph. Stop at the Buc-Wes in St. Augustine, as I approach the light at the top to make the right I feel a a vibration. Almost misfire like. As I get to the light to turn towards the station the vibration gets worse to the point that my stomach sank. However when I step on the gas everything is fine. While at the station, if I fled it a little higher the vibration stopped. So I decided to get gassed up grab some grub and continue. Made it to Boca around 2:00am. After unloading I disconnected the battery and grounded the terminals to each other and went to bed. Funny thing is, when I picked it up after the fix, the “Service Trailer Brake” light kept dinging about every 30 seconds and lighting up the idiot center. After driving it for a while it went away so I’m operating under assumption that the battery was drained. Which would strangely suggest to me that they didn’t disconnect the battery when they rebuilt the top end.

So I am hoping that this rumble/stumble was a result of something needing to be reset to relearn its new improved parameters. Meanwhile, I ordered a tuner from Black Bear and a catch can. I figured since it’s rebuilt I’m going to work with what I can to prevent any issues all while beginning to put collect up parts to put together a NON AFM setup.

Hope for the best but plan for the worst!!

 

[BlaineBug]

Well, I replaced the vacuum pump, swapped out the grill shutter……. This morning At 160,000 the dreaded lifter noise. I’m not sure if it’s stuck, collapsed or what. No idiot light, runs rough, sputtered going up the driveway. This one is beyond my abilities so I have an appt in the morning to drop it at the dealer. Alldata shows 9 hrs for 1 side or 11 hours for both so I’ll most likely opt for all 16 to get swapped out. I will keep everyone up to date.

Question….. Does GM have a DOD delete option or am I stuck with these springy turd lifters and an aftermarket DOD delete? If so does anyone know part #s so I info to ask about.

Dealership service departments will not install aftermarket DOD delete kits, I've asked.

 

[17 Yukon Denali]

Funny thing… installed the catch can yesterday. Pulled the stupid baterang intake and noticed a shiny new LOMA. I don’t think that they would replace that along with all the other parts. Updated to prevent failure perhaps?

 

[BlaineBug]

Funny thing… installed the catch can yesterday. Pulled the stupid baterang intake and noticed a shiny new LOMA. I don’t think that they would replace that along with all the other parts. Updated to prevent failure perhaps?

I believe the procedure is to always replace the Valve Lifter Oil Manifold (VLOM) in the process of replacing the lifters to ensure that the gasket is in good condition and that all of the oil passages are clear and clean.

 

[Marky Dissod]

Dealership service departments will not install aftermarket DOD delete kits, I've asked.

If only dealer service depts had GM approved Engine Half@$$ delete kits ...

 

[Blackcar]

Funny thing… installed the catch can yesterday. Pulled the stupid baterang intake and noticed a shiny new LOMA. I don’t think that they would replace that along with all the other parts. Updated to prevent failure perhaps?

In TSB when repairing Valve train new vlom with different part number is to be installed.

Which in my mind there is something not right with original vlom and I believe there is a different one installed on repairs done today. You might check your repair order to see if the one they installed on your repair has different part number that TSB I linked.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10209953-0001.pdf

 

[Marky Dissod]

In TSB, when repairing Valve train, new VLOMA with different part number is to be installed.

Which, in my mind, there is something not right with original VLOMA, and I believe there is a different one installed on repairs done today.
You might check your repair order to see if the one they installed on your repair has different part number that TSB I linked.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10209953-0001.pdf

Even if GM actually bothered to spend money to improve the Variable Lifter Oil Manifold Assembly,
the root problem is still that the 'Off-On' lifters are not as robust / durable / long-term reliable as
their simpler predecessors that are always On.

(Maybe they should have improved on 'Rhoads' lifters instead?)

 

[Blackcar]

Couple of reads on Valve train.

Tech Tips: Replacing LS Active Fuel Management Lifters With Melling

Replacing a failed AFMt lifter is more involved than just swapping out a bad lifter for a good one - the root cause of the failure needs to be addressed.

www.enginelabs.com

 

[Marky Dissod]

So, GM is so cheap, that not only did they not bother to improve / fix the lifter design,
they ALSO:
1. have pushrods that are too weak?
2. are misaligning the pushrods by cocking them at an angle relative to the lifter?
3. possibly both?

Hang on to your GMT400s & GMT800s, y'all ...

 

[BlaineBug]

Even if GM actually bothered to spend money to improve the Variable Lifter Oil Manifold Assembly,
the root problem is still that the 'Off-On' lifters are not as robust / durable / long-term reliable as
their simpler predecessors that are always On.

(Maybe they should have improved on 'Rhoads' lifters instead?)

The non-AFM lifters fail as well. Although typically the AFM lifters fail in a permanently collapsed state, the non-AFM lifters have the roller seize in place and grind the camshaft down as well. They're all crap. Collapsed AFM lifters seem to cause less damage though as in no damage caused to the camshaft typically.

 

[Marky Dissod]

The non-AFM lifters fail as well.
Although typically the AFM lifters fail in a permanently collapsed state, the non-AFM lifters have the roller seize in place and grind the camshaft down as well.
They're all crap.

I'll stipulate to this after I ask a question:
Isn't it true that the Full-@$$ lifters fail less often than the Half-@$$ lifters?
In other words, aren't Half-@$$ lifters (even) more crappy than Full-@$$ lifters?

 

[BlaineBug]

I'll stipulate to this after I ask a question:
Isn't it true that the Full-@$$ lifters fail less often than the Half-@$$ lifters?
In other words, aren't Half-@$$ lifters (even) more crappy than Full-@$$ lifters?

Some techs have told me they see more non-AFM lifters fail than AFM lifters.

 

[Marky Dissod]

Some techs have told me they see more non-AFM lifters fail than AFM lifters.

Did those techs say that those Full-@$$ lifters were in Half-@$$ / Gen4 V8 engines?
Or Full-@$$ / Gen3 V8s?
Then consider all the techs that none of us will ever speak with.

Gen3 LS / Vortec V8s are better designed, spec'd, and manufactured than
either Gen4 small blocks, or Gen5 / LT small blocks.

 

[BlaineBug]

Did those techs say that those Full-@$$ lifters were in Half-@$$ / Gen4 V8 engines?
Or Full-@$$ / Gen3 V8s?
Then consider all the techs that none of us will ever speak with.

Gen3 LS / Vortec V8s are better designed, spec'd, and manufactured than
either Gen4 small blocks, or Gen5 / LT small blocks.

I thought we were talking about the active fuel management engines. Modern technicians hardly see gen3. Of course, they all agree that they are reliable. However I was specifically talking about the AFM and non-AFM lifters in current generation engines.

 

[Marky Dissod]

I thought we were talking about the active fuel management engines. Modern technicians hardly see gen3. Of course, they all agree that they are reliable. However I was specifically talking about the AFM and non-AFM lifters in current generation engines.

Since we were talking about Engines Half@$$, want to keep Gen3 V8s out of it?
Gen4 V8s with Engine Half@$$, vs Gen4 V8s without Engine Half@$$?
The later still suffer from splayed pushrods?

 

[17 Yukon Denali]

I’m still waiting for a printed work order. I have to call today to see if they finally have access back to CDK. I’ve read that it could months for some places to recover. Thanks for all the info guys. Every little bit helps me better understand the issues we face owning these things.

 

[17 Yukon Denali]

Finally got my printed bill….. if you blow a lifter and gouge the cam…….yeah…. It sucked… Went with Blackbear for the DOD delete and a tune. Installed a catch can and also installed the Trans cooler Bypass. That was super simple and dropped the temp by over 40 degrees.

 

[2015Yukon]

It was nice of them to charge you an additional 199 to put plugs and wires in. You would think since you are taking the cylinder heads off and have to take them off to do so it would be included in CAM/Lifter labor...

 

[17 Yukon Denali]

Yeah…… Took em a whole 5 extra minutes I’m sure.