67Motorcat

Yeah, after seeing the 2nd Video,seems like something more than just the infamous piston slap.

What's the Oil pressure like on your cold start?

JK23112

Your truck is nearly identical to mine -- dark red 2004 with the 5.3L V8 engine.

Anyway, from what I can tell, that sounds like something in the lower end of the engine (pistons, crankshaft, camshaft, etc.). I have no clue as the exact cause or what is making that noise.......but your Silverado should not sound like a Cummins diesel.

I hope you are able to get it properly diagnosed. Meanwhile, try a bottle of Rislone engine treatment or Marvel Mystery Oil. Both can do wonders for a tired engine.

paawwl

Oil pressure is normal during and after the noise goes away.

paawwl

I wasn't due for an oil change but I went ahead and changed the oil yesterday afternoon to see if the oil looked normal or had metal shavings or something abnormal about it. The oil that was in there had about 2000 miles on it and it still looked clean wasn't dark black or anything. I have sent the video's to a couple of different mechanics that I know and no one can really give me an answer. The only constant thing everyone says is - if it was a piston, cam, or other major component coming apart then the noise would no go away once the engine warms up and probably wouldn't last 5 miles down the road. Everyone is baffled as to what could be making this noise.

kevinkpk

Well, not everyone.

paawwl

I was meaning any disrespect. It's just there isn't a constant answer as to what my problem is. I really don't want to start throwing money at this until I have a good guess as to what problem I have. I have heard piston slap before but this seems much louder than that to me, but hell i'm not an expert!

Allan In NE

Aw heck,

Just drive it until a rod comes out the side of the block, the crank breaks in two, or that cap finally comes off. Then, you'll know for sure.

Allan

paawwl

Ok so I just went to run somewhere this morning and since I did the oil change no noise whatsoever... the temp is still in the mid 20's

bandit_601948

that has to be a lifter if it quits after it warms up ! pull the valve pan and check the rockers to see if one is loose ! if it was a wrist pin it would be a double knock, once when the piston comes up and once going back down ! sounds like you have a lifter draining off overnight and it,s taking awhile to build back up !

paawwl

Thanks for the helpful advice!!!