Engine tick, 05 Tahoe 5.3l

So I recently picked up a 05 4wd Tahoe with about 270k. It was a good deal so I said sure why not.

I had noticed a constant low oil pressure and a tick/click noise coming from the engine at around 3k+ rpm. Sounded like the lifters, so I thought if I ran some motor flush and fixed the low oil pressure that might help out the tick. Well a new oil pick tube o-ring and I flushed the engine, but I still hear the tick. Before I tear into the head to check out the lifters and open that can of worms, I thought I would check here and see if anyone might have some tips or tricks. If it might be something else.

Constant any time the engine is running or does it change, like when the engine is warm or cold? Snapped exhaust manifold bolts are common and cause a sound very similar to a ticking lifter. Is your oil pressure good or any better since the new O-ring and flush?

What he said^^^^. I had what I thought was lifter tick and it was an exhaust leak from broken off exhaust manifold bolts. Take a good look at all of them to see if you have any broken ones.

I have had a tick ever since owning my 02. I'm now convinced it's piston slap. From all the reading I've done, I don't think it's anything to worry about.

iamdub said:

Constant any time the engine is running or does it change, like when the engine is warm or cold? Snapped exhaust manifold bolts are common and cause a sound very similar to a ticking lifter. Is your oil pressure good or any better since the new O-ring and flush?

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It's not constant, only at a higher rpm. Once it shifts it goes away. It doesn't seem to matter hot or cold, it still makes the tick/click/metallic clack (one of those sounds lol). Yea oil pressure is way better and constantly above 40 psi now. I was worried it might be the oil pump, but it was the o-ring. It came off in multiple pieces.

sumbum said:

It's not constant, only at a higher rpm. Once it shifts it goes away. It doesn't seem to matter hot or cold, it still makes the tick/click/metallic clack (one of those sounds lol). Yea oil pressure is way better and constantly above 40 psi now. I was worried it might be the oil pump, but it was the o-ring. It came off in multiple pieces.

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Meh. Doesn't sound like an exhaust leak.

Does it at 3,000 RPM, in gear or in neutral/park? You mean it starts at 3,000 and will continue to redline but stops when it's back under 3,000?

This is more of a Hail Mary check, but get a good flashlight and check the flexplate for cracks.

iamdub said:

Meh. Doesn't sound like an exhaust leak.

Does it at 3,000 RPM, in gear or in neutral/park? You mean it starts at 3,000 and will continue to redline but stops when it's back under 3,000?

This is more of a Hail Mary check, but get a good flashlight and check the flexplate for cracks.

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Neutral/park/drive. Anytime it gets to around 3k, below that nothing. did some closer listening, it doesn't really sound like a lifter tick. I'm gonna have someone rev while I listen tomorrow, maybe get a closer listen and see where it's coming from.

Hope it isn't the flexplate. Happened to my Express van with the 4.8. Was a metallic sound. Was cracked almost all the way around the bolt holes of the plate.

Tonyrodz said:

Hope it isn't the flexplate. Happened to my Express van with the 4.8. Was a metallic sound. Was cracked almost all the way around the bolt holes of the plate.View attachment 235224 View attachment 235223 View attachment 235222

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Did you catch that in time or did something bad happen?

Tonyrodz said:

Hope it isn't the flexplate. Happened to my Express van with the 4.8. Was a metallic sound. Was cracked almost all the way around the bolt holes of the plate.View attachment 235224 View attachment 235223 View attachment 235222

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This is bad ju-ju. Kind of a scary thing to see and realize what could have happened if it flew apart at highway speeds. That noise, if it did come apart, would cause a butt pucker for sure.