What are the risks of letting AFM self destruct?

[swathdiver]

I just changed my oil with the Quaker ultimate protection 5w30 and it doesn’t seem to have made much of a difference. Not sure if the standard full synthetic oil would better but might try that for my next oil change


I am wanting to get into overlanding, some rock crawling, etc. nothing too crazy, just going out and having fun on the weekends and going places not a lot of other people are. Since I don’t have 4x4 and just AWD, I don’t see myself doing too much with my Yukon long term. Also the lack of aftermarket support I think would be a hindrance considering I would need some mods to get into more off-road stuff, possible lift, maybe new front bumper since the stock one is super low, etc

I remember our previous conversation now. Yes, Quaker State Full Synthetic has higher viscosity numbers (D445) than what you have now.

You'd be surprised at how capable your AWD rig is as it is. I remember an old TFL Truck episode where they were putting a 2013 Sierra Denali through its paces. It was ripping 14-second 1/4 mile times and going everywhere they pointed it off-road. Of course the reviewer constantly complained about the AWD system but it did everything he asked of it.

As other off-roadies with AWD have stated, you just have to learn to drive them a little differently than a 4x4 and they will go where you want them to. Of course, there's a limit to what a stock truck can do compared with one purposely built for certain terrain/adventures. Tahoe Overlanding on YouTube has some good videos on how he modifies and uses them out in the wilderness.

 

[thefrey]

I remember our previous conversation now. Yes, Quaker State Full Synthetic has higher viscosity numbers (D445) than what you have now.

You'd be surprised at how capable your AWD rig is as it is. I remember an old TFL Truck episode where they were putting a 2013 Sierra Denali through its paces. It was ripping 14-second 1/4 mile times and going everywhere they pointed it off-road. Of course the reviewer constantly complained about the AWD system but it did everything he asked of it.

As other off-roadies with AWD have stated, you just have to learn to drive them a little differently than a 4x4 and they will go where you want them to. Of course, there's a limit to what a stock truck can do compared with one purposely built for certain terrain/adventures. Tahoe Overlanding on YouTube has some good videos on how he modifies and uses them out in the wilderness.

The one I have has a higher kst100 but a lower kst40. I didn’t think much of the kst40 values but maybe they are something I should have paid attention to.

I think that the AWD would do plenty of what I want to do, but I would eventually like to have true 4x4 with lockers. I’ll have to check out that TFL video. I think long term that the break over and approach/departure angles will become a hindrance and I'm not sure if I would want to delete the auto ride to be able to do a lift.

 

[swathdiver]

I think that the AWD would do plenty of what I want to do, but I would eventually like to have true 4x4 with lockers. I think long term that the break over and approach/departure angles will become a hindrance and I'm not sure if I would want to delete the auto ride to be able to do a lift.

That sounds like an older vehicle, a dedicated off-road rig that could do double duty on the street for local driving.

 

[donjetman]

Ignore my squeaky serpentine lol. Doesn’t like to get wet.

Seems to be louder under very slight acceleration. I can barely hear it if my foot isn’t on the gas.

But it’s never that loud when it’s warm. So it could be piston slap.

sounds like something in the valve train (lifter, lifter preload, valve spring broke, valve seat, pushrod).

 

[Charlie207]

Probably not so much. No DI in a 2013? But I notice that 207k miles, that's amazing!

DI started in 2014 for pickup trucks, and 2015 for SUVs. Trucks always get the refresh or upgraded design a year before the SUVs, it seems.

For the cost of an AFM delete kit (~$3000), I was able to buy and rebuild/upgrade a Gen IV 6.0.

 

[Marky Dissod]

For the cost of an AFM delete kit (~$3000), I was able to buy and rebuild/upgrade a Gen IV 6.0L.

Damnt, you've revealed THE best bang-for-the-buck going - deleting AFM from a 6.0L.

 

[morriskb]

Ignore my squeaky serpentine lol. Doesn’t like to get wet.

Seems to be louder under very slight acceleration. I can barely hear it if my foot isn’t on the gas.

But it’s never that loud when it’s warm. So it could be piston slap.

Just got rid of my 2013 Denali XL in February with 310k miles on it. Had a pretty pronounced piston slap on cold start for the last 90k miles but still ran well. Cleared up once the engine reached temp. Tuned out AFM in 2017 but left the hardware in place. Never had an issue. Got rid of it only because it was in need of transmission #3. Hands down the best AWD out there too. My 2018 replacement doesn’t have the same confidence inspiring performance as the ’13.

 

[Charlie207]

Just got rid of my 2013 Denali XL in February with 310k miles on it. Had a pretty pronounced piston slap on cold start for the last 90k miles but still ran well. Cleared up once the engine reached temp. Tuned out AFM in 2017 but left the hardware in place. Never had an issue. Got rid of it only because it was in need of transmission #3. Hands down the best AWD out there too. My 2018 replacement doesn’t have the same confidence inspiring performance as the ’13.

Define "confidence inspiring". I'm probably going to be looking at a K2 Yukon in a few years.

 

[morriskb]

Define "confidence inspiring". I'm probably going to be looking at a K2 Yukon in a few years.

Your best bet would probably be to jump to the current gen with a diesel. I bought a meticulously maintained example with 94k miles on it. The transmission hiccups are random, the engine will randomly idle funny (dealer told me that’s common for the 15-20). Infotainment glitches are rare, but can be frustrating when they crop up and will require a restart of the vehicle - which I’m not pulling off the highway special for when on a long trip. It’s not one specific item that I can put my finger on, but everything about it combined doesn’t give me the confidence that it’ll last nearly as long as my last one.

 

[Smokin Denali]

My 6.2 likes to tell me knock knock jokes about its top end in the mornings… I don’t particularly appreciate this when I’m half awake heading to work LOL

Even my wife noticed one morning… I feel like if your wife notices when something is wrong it’s not right

Everyone says it’s the “Chevy tick”, so don’t know how much a red flag listening to the knock knock jokes are



So… is there any harm in letting AFM self destruct? If it’s going to die, all the parts are going to get replaced anyways.

I don’t particularly love the Denali platform with the AWD looking forward to what I want out of a vehicle. Great for daily driving, but I am wanting something more off-road capable

I mention this because I don’t know if I’m interested in making this a 300k+ vehicle for myself. I got a quote to delete AFM from a local shop (3k). I realistically see myself driving this vehicle for another 25-50k so 1-2 years.

If I can, I want to ride it out to see if I can keep AFM when I sell and so I can put the $$ into another vehicle maybe.

Edit: another view perhaps is I’m trying to determine if I can ride it along with AFM for a little while, or if a new to me car should be first thing on my radar.

FYI......y 2025 Yukon Denali 6.2L, with 48k gave its ALL, as I gunned it, to cross a 3 lane intersection at Rush Hour@ I only made it 10' into oncoming traffic and Limped across the rest, narrowly avoiding a nuts and bolts Hail Storm massage.
Dumped my 5th and last Denali 2 years lateto avoid pressing my luck, 11pm, on a Beruit Blvd somewhere w family in truck.
Bye bye GM.......

 

[Smokin Denali]

FYI......y 2025 Yukon Denali 6.2L, with 48k gave its ALL, as I gunned it, to cross a 3 lane intersection at Rush Hour@ I only made it 10' into oncoming traffic and Limped across the rest, narrowly avoiding a nuts and bolts Hail Storm massage.
Dumped my 5th and last Denali 2 years lateto avoid pressing my luck, 11pm, on a Beruit Blvd somewhere w family in truck.
Bye bye GM.......

Error! It was a 2015 !!! Not 2025!!

 

[PG01]

Define "confidence inspiring". I'm probably going to be looking at a K2 Yukon in a few years.

Charlie, 18-20 k2’s are fine… id even say 17’s but people will probably disagree with me.

 

[Charlie207]

Charlie, 18-20 k2’s are fine… id even say 17’s but people will probably disagree with me.

I consider the K2 Yukon the best looking version of the Corporate Motors SUVs; much better side & front 1/4 profile than the goofy Tahoe front-end. It's like they were trying to look like a 5th-gen Camaro V6, or something. But what do I know?.... I drove a 2014 Yukon that looks like a Terrain or Acadia front-end.

I just don't want another IRS chassis, unless it is the amazing Gen4 Montero Ltd, with its nifty 4wd system.

 

[GMCChevy]

I consider the K2 Yukon the best looking version of the Corporate Motors SUVs; much better side & front 1/4 profile than the goofy Tahoe front-end. It's like they were trying to look like a 5th-gen Camaro V6, or something. But what do I know?.... I drove a 2014 Yukon that looks like a Terrain or Acadia front-end.

Funny if anything I see it as the opposite with the Yukon looking more like the goofy one with the start of GMC grilles that are too big to fit the front properly and the headlights that carry on the tradition of being ugly from the last generation lol. The rest of the side looks identical.
The Tahoe front is a bit on the bland side.

They both look strange with the over sized wind deflector.

 

[Charlie207]

Funny if anything I see it as the opposite with the Yukon looking more like the goofy one with the start of GMC grilles that are too big to fit the front properly and the headlights that carry on the tradition of being ugly from the last generation lol. The rest of the side looks identical.
The Tahoe front is a bit on the bland side.

They both look strange with the over sized wind deflector.

Wouldn't it just be smarter to ignore focus-groups and soccer moms, and just use the Sierra and Silverado front-clips?

 

[GMCChevy]

Wouldn't it just be smarter to ignore focus-groups and soccer moms, and just use the Sierra and Silverado front-clips?

That's it too.. I never hsd a problem being identical to the trucks but enclosed rear. Heck the soccer moms didn't either cause they've been driving them since the 90s.

That being said I don't like the current truck styling much either.

 

[Charlie207]

That's it too.. I never hsd a problem being identical to the trucks but enclosed rear. Heck the soccer moms didn't either cause they've been driving them since the 90s.

That being said I don't like the current truck styling much either.

I just want the same aftermarket/off-road bumper options the Chevy's have.

 

[thefrey]

sounds like something in the valve train (lifter, lifter preload, valve spring broke, valve seat, pushrod).

Do you have any tips for diagnosing any of these issues?

I don't really know what to look for. A mechanical stethoscope may help me hear it better, but I don't think that will (personally) help me as this is beyond my knowledge per se. I know the valve spring is not broken and the pushrod is not bent from when I unstuck the lifter.

I have had this tick since I got the truck. It has usually been intermittent, but I recently have noticed it more. I don't think it's getting louder, just seems to be happening more consistent. I would sleep better at night if I at least knew what the issue was...

I believe the noisy lifter is the one that I had collapse. I unstuck it and tuned out AFM and it's been 10k miles, but it was kind of noisy intermittently before it collapsed. It collapsed after I replaced my pickup o-ring, which in turn increased oil pressure and made AFM more active. Last owner said he replaced the lifters, so they should only have 30k or so on them.

My guess is that maybe the last owner collapsed a lifter, so there might be a flat spot on the cam. He probably didn't replace the cam when he put new lifters in.

Edit: just thought about this... no clue if this would make a difference, but when my lifter collapsed, I cut the gaskets on the VLOM as a secondary failsafe so there would be no chance of oil pressure accidentally building up on one of the towers. This might sound stupid, but maybe since that lifter now has no oil pressure on it, so it doesn't have a chance to "pump up" and is causing slack in the top end? No clue if that's how it actually works. Just some food for thought.

 

[Marky Dissod]

If I'm wrong, mods feel free to delete, but on neither page do I see word one about any exhaust manifold leaks; sound suspiciously similar to lifter tick ...

 

[donjetman]

use the search feature here with words like "Preload", etc
and
youtube is your friend