Bought a 2008 5.3 with 300k kms. Had a P0304 and some o2 codes. Pulled valve covers off and #4 exhaudt lifter is collapsed. Took head off before I found your site. Lifter is in 2 pieces. Roller and cam both look good. Screen on vlom is clean. Wondering if I can replace the afm rollers with oem afm rollers on this side, order your oil sensor block and do your vlom mod? And be ok for a good while? Will also diasble afm with an hp tune? Thanks
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Yes, as long as it all checks out use oem replacement lifters. Just make sure to stick to AFM lifters with the AFM camshaft. VLOM mod and tune would just be a bonus to help prevent failures of the system.
I have a 2009 hybrid with AFM, and DOD. I tried the lifter trick 1st, but it was too far gone. The locking tab was too far worn. I bought new dog lifters and replaced them, 3 TIMES!!!
I had 1st set where 1 lifter was locked and wouldn't open. 2nd time, and another new set, one of the lifters had a weak spring, so it was just clicking all the time, and made the check vall seal poorly, so it would bleed down super easily.
3rd time, and another set, one of the new lifters was machined poorly, and wouldn't push any oil up the pushrod to lubricate the rocker.
Finally, I mixed and matched the 3 sets of lifters, and hooked my DIY Pressurized oil tank upto the oil plug port on the side of the block. (Thr one people use to prime the ls engines) and pressurized the system with 60psi of oil and left the heads off so I could see the oil move thru the lifters, then while under pressure I used an old pushrod with a handle I made, to try and manually collapse the lifters. Once all tested good, I buttoned up the motor with new head gaskets. On the hybrid, HPTuners can't disable the dod system, but the little things that plug into the obd2 port will, so I run that all the time, on an extension, so it's tucked up under the dash.
Moral of my story. Buy the expensive lifters and even then.. check them completely before final install.
Was the lifter roller damaged at all? You can do the VLOM mod after replacing lifters with stock AFM lifters. You will need a tune to do it though. I recommend lt1swap.com for the tune.