AFM lifter fail on my 2018 Yukon Denali

[CMoore711]

Those SS Sedans are rare. What prompted you to remove the clear bra from it?

Also; What did you end up doing on the Yukon Denali tune-wise to turn off the AFM in the tune?

 

[MrMonte]

Those SS Sedans are rare. What prompted you to remove the clear bra from it?

Also; What did you end up doing on the Yukon Denali tune-wise to turn off the AFM in the tune?

The 10 year old clear bra wasn't clear anymore & my wife was on the hwy and something hit the driver's fender so I repaired it & painted the driver's fender 3 weeks ago. Plan is to do a 2000 grit wet sand on whole car, buff then ceramic coat.

I tuned out AFM using a F5 Flashpaq tuner about 30K miles ago. My mpg actually improved from an overall avg of 20.1 for the 1st 60K miles to 20.3 for the last 30K. Time will tell with the new cam and all that carbon buildup gone.

 

[MrMonte]

Here's a cold start after my AFM delete with new cam & lifters. Temp was 40°F. Overall driving experience has improved. Does feel like I got a bit of a power increase across the whole rpm range. Throttle response seems better too.

 

[fasteddy]

Good walkthrough! Thanks! How many hours did that take you, in work? 30-40? And you didn't change the tune for that cam? Just DOD "tuned" off? I am procrastinating on mine. I have decent ticking on the driver's side, and has for about 10K miles. Ticking like a time bomb. LOL. Thanks again.....I hate DOD. I have 90K miles and DOD has been off since 50K.

 

[MrMonte]

Good walkthrough! Thanks! How many hours did that take you, in work? 30-40? And you didn't change the tune for that cam? Just DOD "tuned" off? I am procrastinating on mine. I have decent ticking on the driver's side, and has for about 10K miles. Ticking like a time bomb. LOL. Thanks again.....I hate DOD. I have 90K miles and DOD has been off since 50K.

I've been using the 91 octane performance tune with AFM deleted via the F5 Flashpaq tuner for last 30K miles. Didn't change the tune after the cam swap. May do a dyno tune someday.

The AFM delete took me about 20hrs but I didn't drop the oil pan. I did another AFM delete without dropping the oil pan after doing mine and was able to complete in about 15hrs. Walking the chain off/on is easy for me now.

 

[MrMonte]

Doing some 100+ mph pulls on the Yukon I got a couple of cylinder #1 misfires. Found some arc traces on #1 spark plug which was new 1,500 miles ago so I replaced it & all is good again. New parts going bad is so common & frustrating.

2/3 of my drive to work is a curvy hilly hwy that goes thru 2 small towns (25mph) but no stops (pic1) & remaing in towns with many stop lights which I hit 15 of the 17 red lights tonight (pic2). Still did pretty good on the gas mileage.

I have 1,500 miles on the new cam/lifter setup & also did a transmission fluid/filter and have been enjoying the extra power that I wasn't expecting. Since this is my daily I didn't want a lopy cam & the power curve with VVT is so much better. The improvement in mpg
was a pleasant surprise.
My best driving to work has been 27.7mpg (only hit 6 red lights) where before cam was 25.8mpg.

 

[fasteddy]

Thanks for the update. I want to try that cam. The Lower lift and bigger fuel lobe must be giving you more lower end TQ, which is translating into increased responsiveness with less throttle, thereby also the better fuel mileage. I have all my parts now except for the cam but I can't find that 4572 cam anywhere. sheesh, the strike kinda wiped out OEM inventory. Did you do anything with that valley cover or just put it back stock?

 

[MrMonte]

Thanks for the update. I want to try that cam. The Lower lift and bigger fuel lobe must be giving you more lower end TQ, which is translating into increased responsiveness with less throttle, thereby also the better fuel mileage. I have all my parts now except for the cam but I can't find that 4572 cam anywhere. sheesh, the strike kinda wiped out OEM inventory. Did you do anything with that valley cover or just put it back stock?

That 4572 cam was backordered everywhere so I got the cam in link below which is in stock.

SDPC SDR29512 - L86 Gen V DOD/AFM Delete Camshaft

Are you removing AFM/DOD (4-cylinder mode) from your Gen V 6.2 L86 engine? Pair this camshaft with our AFM delete kit and a set of new non-AFM lifters and you have all of the hard parts necessary to

sdparts.com

I plugged the AFM oil ports then installed the AFM valley cover & everything is connected even though it's not being used.

Doing the AFM delete was for peace of mind. The extra power & mileage were a welcome bonus.

 

[fasteddy]

Cool. That is the one they actually sell with the kit. I'll get that one too. Thanks again!

 

[MrMonte]

Cool. That is the one they actually sell with the kit. I'll get that one too. Thanks again!

I only bought the cam from them & bought parts separately which ended up being cheaper for me.

Make sure to get AC Delco lifter trays as some of those cheaper ones may allow the lifter to rotate & fail.

You should replaced

GM Genuine Parts 12589016 Camshaft Retainer​

The seal on mine was pretty flat which can cause internal oil leak.

There's alot of opinions on lifter choice. I went with AC Delco LS7 lifters, reused my pushrods that were still good, didn't have to change valve springs or mess with the VVT.

I paid $270 for my trays & lifters. Cyber Monday has some cheap trays & lifters for $70 which I would be afraid to use. Seen reviews on some of these cheap sets where the new lifters failed within days if not hours.

GM OEM LS7 LS2 KIT: 16 Lifters... https://www.amazon.com/dp/B07545W1K6?ref=ppx_pop_mob_ap_share