2007 Silverado Classic 5.3 non AFM engine tick/knock

opeg1979 · March 18, 2022

5.3 NON AFM with the like 210k

I know this is issue is common and probably on here a ton, but I am just not sure what this issue is and I thought I would see if anyone as had this specific case. Had a knock sensor code a month or so ago but it went away on its own. What is happening is every time I drive the truck it goes though this cycle where it ticks. Idling, driving i hear it. Seems to happen faster when sitting still. Then all of a sudden it goes way. Oil pressure is ok, i have tried thicker oil, motor flush twice. I thought it was oil pickup tube problem, but the pressure is good and i had another truck with that issue and it was not the same. I figured its a stuck lifter but if that were the case why does it stop and start again? Just wanted to get some opinions before tear it down. That is the one things that baffles me is that is stops, and it can start anytime, cold or hot. It does seem better for a while after a fresh oil change. How bad is running it with that tick long term?

Thanks,

CamGTP · March 18, 2022

The lifters don't really "stick" on these ones because they don't collapse like the newer lifters do in the AFM/DoD engines. They just get noisy because they may not stay pumped up with oil and you hear that sound.

I had a Sierra with over 250k miles on it, it made a ton of lifter noise. Sounded like a sewing machine all the time and it kept on going. Never got louder or showed any signs of metal in the oil so I never took it apart.

Your other thing to check is for broken exhaust manifold bolts, a minor leak in the exhaust can sound like an engine problem as well. So your options are to either deal with it or pull the heads to replace the lifters and inspect all the camshaft lobes for wear.

Edited March 18, 2022 by CamGTP

dna9656 · March 23, 2022

Read my posts. I replaced the o ring at the pick up tube oil pump connection. While there I replaced the oil pump with a high volume Melling pump, the timing chain/ gear, and the pick up tube.

Edited March 23, 2022 by dna9656

opeg1979 · March 24, 2022

@dna9656 thanks for the reply. I was hesitant on that being the issue because a friend just did this and it did not fix the sound in his 5.3, but I will check out your posts!

dna9656 · March 29, 2022

It's involved but not hard to do, it'll take a good or 2 depending on what you do. As I might have said I replaced the timing chain and gears, installed a Melling Hi Vol oil pump, along with the O ring thing. Do a search for this: "Oil Pump Girdle Pickup Tube Brace/Girdle for LS Engine LS LS1 LS2 LS3 4.8 5.3 6.0L" on Amazon; this way you'll have it (the oil pickup tube) more than safely installed. Don't forget the lock tight and a torque wrench either! If you replace the t chain you're going to need a harmonic balancer puller for a 5.3 (if that's what you have...)

Edited March 29, 2022 by dna9656