Jake Wade

Sounds like loose torque converter bolts.
The speed sounds too fast to be valvetrain.
I am going with bottom end. Hopefully not a rod bearing.

Darth_V8r

iTrader: (4)

I went back and listened to my failed lifter videos. The sound was slower and not near as deep. I hope the others are right and it's a converter bolt.

Sounds similar to rod knock to me but your oil pressure would not be good if it was.

Another vote to cut open the oil pan edit; filter

mtubbs

well before I left for work this morning I decided to go ahead and pull the valve cover and take a gander... all was clean and clear of debris and looked to be ok as far as the rockers and push rods... didn't have enough time to go deeper into diagnosing anything really other than shaking around the rockers to see if I have to much or not enough play and I'm noone nor a mechanic just mechanically inclined.. but it seems like I have one or two Maybe a little loose ... could that cause the knock that I have or do I need to go deeper... 🤦.. new to the makeup of the LS engine... I've done alot of work on them just my first tear down.... gimme an old sleep 400... 👍... just got to much in and no more time... I need my truck back on the go... it's my towpig... lol...

01CamaroSSTx

iTrader: (3)

Really hard to distinguish from a video and I'd like to be think that I'm mistaken.

CattleAc

iTrader: (7)

This would be my vote also if he hadn't just rebuilt it...


I bought a 6.0 from a guy for almost nothing that sounded just like that...had a broken flywheel...

mtubbs

https://youtu.be/TzVG3QexIBscheck it out and gimme your thoughts...🤬😤... the knock I'm concerned with starts around 0:50

tblentrprz

I hear a light tap at :50 and heavier tick at 1:08. Hard to say what's going on. If you did not find anything when running without valve covers not sure what to say. An experienced tech with a stethoscope is needed to locate root cause.

SCJW

Does it change when you rev it? You may have to drop the pan and see what's going on at this point.

mtubbs

it does pick up with rpm and gets a little quieter until you let off the gas

SCJW

Any updates on this?

mtubbs

not yet... haven't had a chance to get back to the truck yet... soon as I do I'll update

mtubbs

changed out the flexplate yesterday and 🤞seems to have gotten rid of the knocking... gotta hook the transmission back up and see where we are... I'll let y'all know when it's done and if it took care of the issue

SCJW

That’s great news. I hope it works out.

cam

iTrader: (9)

Derp, didnt see second page. Post another vid

mtubbs

... ok.. so, I replaced the flexplate and finally drove it a few blocks... got back home and this happens... the video shows what it sounds like now... compression, oil pressure, spark and fuel seems to all be good... clean oil... 91 octane fuel... seems to be a little slow on acceleration with higher rpm shifts... dipstick shows full... but added a half quart of trans additive... and oil additive.. as well as fuel treatment... could it be torque converter or input shaft bearing??? just wish the knock would disappear.... 🤷😤🤦

mtubbs

at the very last second of the video it kinda sounds like something settles like a bolt or something being tossed around inside a metal can and then sit down and it rattles a little before settling... but idk... thinking about just sending it to the scrap yard or setting it ablaze

cam

iTrader: (9)

Man I hate to say this but it sure sounds like a rod. Drop the oil and see if there is any shiny metallic content or as mentioned cut the filter open and see. I aint for sure on nothing from my ears though so its a take things apart til ya find it kinda deal. No fun at all and if its any consolation i've been there before, a few times, heck twice in a row same build once.

Old Buzzard

Pull each plug wire and listen for a change in noise......

mtubbs

I have disabled each individual coil pack one at a time and the only change in knock is on cylinder 5 and it gets worse... I've always been told that if the knock goes away then it's rod knock and if it goes away it's fuel related or valve train... this is my first build of an LS engine so I'm not to familiar with it but have done alot of work on them and topends... but my first complete rebuild... I've pretty much always had 350 & 400 sbc... I bought the truck for a steal and haven't really had to do to much other than the rough driven, offroading frontend parts that have normal breakdown with this truck due to the aggressiveness of it's setup vs. it's poorly engineered frontend parts... which will eventually be beefed up... it's had a bad head gasket since I've owned it luckily on exhaust side ... year and a half to 2 years later I decided to fix the issue and ended up having to replace both heads.. one of which was cracked previous to tear down and the other done "accidentally" during tear down by little helper...😤🤣🤷🤦....... replaced an injector or two, all gaskets/seals, all sensors, pistons and wrist pins, bearings, thrust plate oil pump, water pump, power steering pump and pulley, high output alternator, long tube headers with 2 1/2 inch turndowns and rear of cab, cats deleted, rear o2 deleted, new flexplate, starter, only thing original is the block, crank, cam, lifters and pushrods as well as the intake and throttle body and harmonic balancer.... even added the Accel super coils... could this be a spark issue with having performance coils on a stock air and fuel intake system... and I just remembered that the regulator on the fuel rail was disassembled while under pressure.. again little helper 🤦... I don't know if you can tell in any of the videos but bank one header does seem to be getting a little to hot as bank 2 seems to be running normal maybe even a little cool.... but like I said I'm not familiar with the building of the LS... gimme an old skewl sbc and I'd say check for a cracked/leaky intake.... then move down... but... this is a computer controlled LS LQ4 🤷🤦🤬

mtubbs

... the latest video...🤦... changed oil... and...🤦