08 tahoe lifters issue (video)

2008 Chevy tahoe 181k mi
dod lifter on cyl 6 collapsed when I was on the highway, pulled to the side and towed it home.

I replaced all 8 lifters on bank 2, guides, gaskets, high volume oil pump. cam had no damage signs.
after putting everything together, i had constant misfire on cyl 4&6 the dod ones.
I did a smoke test, no leaks, swaped coil, spark plugs and wires, replaced injector connector, no change.after removing the valve cover i turned the engine by hand and saw all lifters moving but when i crank
the engine with the starter, none of the rocker arms on cylinder 4 and 6 move as seen on the video. if the engine hasn't been turn for 20-30 minutes, (im guessing when there is no oil pressure) the rocker
arms on all cylinders move 2-3 times and then cyl 4&6 stop. It seems like they are always getting oil pressure and deactivate. I did not replace the vlom, thinking if this is the issue?
When i had the collapsed lifter I only had a misfire on cyl 6, not on 4 like i do now.

any help is highly appreciated.

my first question would be where did you buy the afm replacement lifters? it's pretty common for non oem or millings to he bad out of the box.

if not, and you have good lifters replacing the vlom might help, better yet would be deleting the whole afm stuff or atleast doing the disable in the ecm, the oil passageway plug and cut the gasket to vent oil pressure going to the lifter.

you wouldn't have afm, but it might keep the lifters from releasing from oil pressure unless you have bad new lifters.

j91z28d1 said:

my first question would be where did you buy the afm replacement lifters? it's pretty common for non oem or millings to he bad out of the box.

if not, and you have good lifters replacing the vlom might help, better yet would be deleting the whole afm stuff or atleast doing the disable in the ecm, the oil passageway plug and cut the gasket to vent oil pressure going to the lifter.

you wouldn't have afm, but it might keep the lifters from releasing from oil pressure unless you have bad new lifters.

Click to expand...

I did get melling lifters. Im a mobile mechanic and never had any issue with this brand but there’s always a first time right? Im just thankful it happened on my daily truck and not on a costumer vehicle.
I just got my vlom right now, and from what i can see, the gasket on my old vlom is far too gone, I will install it and give an update later on today.
If vlom doesn’t work, i’ll just delete the afm system

yeah. millings is supposed to be good stuff.


definitely let us know if replacing the vlom works. not to many people replace that. usually they just delete by this point. for a very. short time I thought about replacing the vlom on mine when I first got it with no lifter issues and see if that was enough to make the lifters last but I soon decided it is to more risk vs reward and just disabled the system best I could.

with one of those cyl on tdc can you push down on the push rods by hand? meaning the new lifters are stuck already?