THE-HOE

iTrader: (3)

Well I finally got a dyno tune, and a day later my engine began to knock. It will only knock at about 25percent load and more. At idle and under light crusing it is silent. It still has perfect oil pressure also. I had to drive it about 5 miles with this knock then i shut it down and called a tilt-bed.

The knock did not come from one speficic side of the engine, and when i crawled underneath it it was alot louder. So i assumed it was in the bottom end.

I dropped the oil pan and found some slight hints of metal in the pan, nothing huge. I took some pictures of the bearings to hopefully see if you guys could tell me if they look like they have gone bad. This motor has about 45k on it right now. Pics are below, Thanks in advance for the help, this is just too much bad luck lately.

TIM Z

iTrader: (12)

Bud i hope you have some better luck soon, you deserve a brake.

Is the scoring deep in the bearings?

Wander if you may have bad rods???

Not sure but following along.

And where in PA did ya get a dyno tune?, just curious

TXSZ66AVLANCHE

iTrader: (7)

They look fine in the pictures, there is plenty of other stuff that can knock though. Mine sounded like the bottom end and during tear down it was all camshaft and lifter issues making the noise. Did you pull all the caps?

THE-HOE

iTrader: (3)

No the scoring is not deep at all, i cannot catch a finger nail on them. I got my tune at Rodeheavers, they were having a dyno day. The tune went really well and the tahoe put down good power. Ill start a new thread about it a little later.

No i did not have time to pull all of the caps, i will be doing that this weekend. My only concern is that I cant pull the very last main cap with the engine in the vehicle, because the cap goes under the rear cover on the engine ( whatever that's called)


Do rod or main knocks usually knock all the time or will they go away at idle like this?

Mangled03gmc

iTrader: (95)

They look ok to me, but it's just pics.. Run your finger nail over them, if it hangs up, they should be replaced. If they are out I would replace them just for safety, they are cheap

THE-HOE

iTrader: (3)

What brand would you recommend? I have never replaced bearings before so it scares me that I will mess them up. I cant just take the old ones out and put the new ones in can I?

JFOLM

iTrader: (8)

sub'd

mechan12

yes you can if it is not scored and every thing must be clean ,clean,clean,
then you must check the clearance on the bearings after that you clean again and use some ***. lube then bolt it all back together to the right torque settings
donald

Callies Performance

ACL or Clevite

TXSZ66AVLANCHE

iTrader: (7)

Typically no you can't just replace the bearings, you need to polish the crank and install over sized bearings. As a last ditch effort to patch it up while still in the truck? Go for it....after u have pulled all the rod caps, if nothing is obviously wrong with the rod bearing it will be pointless to replace em.