2006 5.3 knock after highway driving
 

It's been a while since I've been on here, but here it goes..

​​​​​ 06 has a mean tick/knock that only happens during and after highway driving at ~2k rpms. Always at full operating temp. Bone stock minus drop in filter. 06 ecsb 5.3/60e/G80/3.73s with 215k. Chimes low oil pressure on cold startup and oil pressure slowly climbs for a few seconds until it stays around 25-30psi at idle. Ambient temps between 80-95. The knock/tick is typical of a 5.3 on startup, maybe a little more fierce but not awful. The weird part is that the knock occurs after driving at highway speeds ~70mph @ ~2k rpm for a few minutes and it does not go away, even after reducing speed and rpms in town. I have a video that I'll try and post for reference.

I'm thinking oil pump, pickup tube, pickup o-ring. I had another 5.3 that knocked hard as shit on startup so it was parked. I did oil pump and pulled the pan, cleaned pickup tube etc and that helped, but I'm concerned that this may be unrelated to an oil starvation issue. The last pickup tube I pulled was God awful. You could barely get air through the tube.

Idk fellers any help would be appreciated. I'm worried I'm going to have to bite the bullet and pull the pan, but I'm hoping that's all it is. Thanks.

https://streamable.com/aegl3j

Is that maybe a lifter?

Damn that is loud. Have you cut open your filter to check for metal?

Update: Pulled the oil pan and pickup tube. Replaced oil pump, timing chain and gears, water pump, all gaskets related. There was a tiny bit of metal on the drain plug but nothing significant.. I ended up using the 295 high volume oil pump. At idle I'm now around 60psi. Did an interstate drive last night and there's no noise whatsoever. I'll keep this thread going with updates. Really hoping it's fixed, because if it's not..well I'm just going to 6.0 swap it at this point.

To anyone reading the his that has never changed the oil pump on a 4wd: The front diff has to be removed or lowered enough to take the oil pan out. There are three points of attachment..passenger side has 2 studs with a washer and a nut, driver's side has one bolt and nut, and there is a front mount with one nut and bolt on the driver's side that can be accessed from under the front bumper by jacking the truck up a little more. The front mount is by far the toughest one to get loose, as there is very little room to turn your ratchet. This is my second truck with this issue, and I swore after the first I'd never do another lol.

Oh Man! 🤞

I was guessing lifter because you said only does it after driving on the highway over 2k RPM. Maybe the increase in oil pressure is helping there too.

I think a rod knock would do the knocking all the time, and sound increases with RPM. I think mains would just spins a bearing and that would obviously be the end of the engine.

Okay that makes sense. Thanks for the reply. And yeah, that's the weird thing; it only did it after sustained RPMs over 2k. It hasn't made any noise yet. I'm hoping the issue was fixed but we'll see.