New gmc member from CT

[Ss1018]

The AFM components are the same or nearly so. There are improved parts now that offer greater reliability but I do not know what year engines got those or if they were introduced as replacements. It is best to remove AFM physically from the engine as the De-Ac lifters can still collapse even if not used for dropping cylinders. Even the non-AFM lifters have been known to fail, around Christmas two Denalis on this here forum had them fail and needed replacing. Dirty oil however is the engine's worst enemy as is sludge. Many develop problems because they bought a truck that had had regular crappy oil in it and changed it every 7500 miles, long after it was dead. Then the new owner comes along and puts Mobil One synthetic which begins to loosen and clean all that crud out and it starts moving through the system and creates problems.

At the very least get one of those Range AFM devices or preferably a BlackBear tune. Then when you can, tear down the top half of the engine and remove the AFM components and put in a new camshaft. Then you'll have Gen III reliability with Gen IV durability.

The AFM components are the same or nearly so. There are improved parts now that offer greater reliability but I do not know what year engines got those or if they were introduced as replacements. It is best to remove AFM physically from the engine as the De-Ac lifters can still collapse even if not used for dropping cylinders. Even the non-AFM lifters have been known to fail, around Christmas two Denalis on this here forum had them fail and needed replacing. Dirty oil however is the engine's worst enemy as is sludge. Many develop problems because they bought a truck that had had regular crappy oil in it and changed it every 7500 miles, long after it was dead. Then the new owner comes along and puts Mobil One synthetic which begins to loosen and clean all that crud out and it starts moving through the system and creates problems.

At the very least get one of those Range AFM devices or preferably a BlackBear tune. Then when you can, tear down the top half of the engine and remove the AFM components and put in a new camshaft. Then you'll have Gen III reliability with Gen IV durability.

ah finally a real answer. I know the base vortec engine in these things is solid I just have no experience with afm. I know the dealer changed the oil just before I bought it but I have no clue what oil was used. Most likely non synthetic tho. I plan to use Mobil 1 because in my opinion it’s top notch and matches the dexos or whatever requirement there is. My only question is is there any other symptoms to failing lifters besides the ticking and running like crap that I should look out for?

 

[swathdiver]

Not usually, maybe low oil pressure. Oil pressure gets low with dirty oil too. Look for misfires on a scan tool. When they're subtle I think we cannot see or feel them, only the scan tool can pick them up. Thankfully mine has had zero misfires so I have no experience with them on these engines. I've been a believer of synthetic oils and Mobil One since the 1980s.

 

[Ss1018]

Not usually, maybe low oil pressure. Oil pressure gets low with dirty oil too. Look for misfires on a scan tool. When they're subtle I think we cannot see or feel them, only the scan tool can pick them up. Thankfully mine has had zero misfires so I have no experience with them on these engines. I've been a believer of synthetic oils and Mobil One since the 1980s.

Ok I just wanted to make sure. I have no problem replacing lifters I just wanna catch the issue before a valve spring or something catastrophic happens. I’ve read a story or two about that. I won’t bother you or anyone else at the moment but when I’m ready I’ll probab make another post on what items I should remove/replace with the afm beside the lifters and cam shaft. I know there’s an oil pressure solenoid and so on involved with it but I’d like a good list with maybe some good part numbers if I can get lucky lol. Thanks so much for the helpful info so far.

 

[Fosscore]

Welcome. Nice Denali and congrats on kid #2.

 

[swathdiver]

You're welcome. I've made a list of part numbers for when I do mine, but you'll have to change some up for your 6.2, like the head gaskets.

 

[Doubeleive]

I turned mine off with a tune, didn't see any mileage difference

 

[08grey]

No mileage difference. Let's just say dobt ever pay attention to the mpg your going to get and you will be a happy camper.

These trucks will tick and slap and just keep going. Don't worry about too much big failure. Get a catch can. This will help. Always let it warm up before you go out. You can get a VCIM from a newer truck and turn on the free on star app and start from your phone.

Sent from my SM-G950U using Tapatalk

 

[Ss1018]

I turned mine off with a tune, didn't see any mileage difference

Sweet. I don’t care if I lose 1 or 2 mpg I just care about reliability. I do mostly highway driving and I don’t tow at all so the engine is pretty much never beaten on now. I don’t know how it was driven before me.

 

[Ss1018]

No mileage difference. Let's just say dobt ever pay attention to the mpg your going to get and you will be a happy camper.

These trucks will tick and slap and just keep going. Don't worry about too much big failure. Get a catch can. This will help. Always let it warm up before you go out. You can get a VCIM from a newer truck and turn on the free on star app and start from your phone.

Sent from my SM-G950U using Tapatalk

Thanks man. I read that supposedly Gm fixed some issues by 2010 With the afm but I’m not totally convinced. Not to sound like an idiot but what exactly is a catch can?

 

[PG01]

Thanks man. I read that supposedly Gm fixed some issues by 2010 With the afm but I’m not totally convinced. Not to sound like an idiot but what exactly is a catch can?

Its supposed to grab the blow-by oil from entering your intake ...plumbed into the pcv system
https://www.performancetrucks.net/f...21/pcv-oil-catch-can-n-5-3-fills-fast-455782/