I hope they replaced it under warranty!!

 

I would guess a bearing on the rod. I replaced a piston once before in a 6.0L for this reason: the side of the piston, the skirt, broke completely off and it knocked like a son of a gun. No damage to the cylinder wall, replaced the piston and it's been seeing abuse for several months now.

good luck and attempt the fix yourself, you have enough support on the forum to get by.

allen

 

Not to get off topic but did you swap the piston out while it was still in the truck/car?

 

I was going to ask the same thing. Who is doing the tuning for you? Have you done any logging with the LS1 motor? Good luck bro.

 

this is not always the case. I have done 2 rod bearings on 2 seperate trucks while they were still in the truck. they are still running today. often times spun bearing are a result of poor oiling, that is why I recommended him replace the oil pump and all the main and rod bearings. the 2 that I replaced in both cases the owner shut the engine down as soon as he heard the knock. I would think as long as the bearing spun and didn't come apart there should be no crank damage as long as you shut it down immediately. remember the bearings are softer than the crank.

in this case with him driving the truck home there may be some scoring on the crank journal. either way it really is not a big job. If you feel more safe yanking it and putting it on a stand then by all means do it. I was simply trying to save him the hassle of dealing with wiring/hoses, etc to yank the engine. Then again I am not there and cannot asses the situation personally.

If it were me I would pull the pan first with the engine still in the truck. If the crank is phuct you have lost nothing and can still yank it. If however you go to all the trouble to yank the engine and flip it only to find that the crank is fine and it only needed bearing well you might feel a little like

Are you absolutely sure the engine was not low on oil. insuffecient oil level is to blame alot of times too. It could be the oil pump but highly unlikely. another good possibility is the pump pickup being clogged with debris. Believe or not in one of the trucks above I worked on when the owner put the oil pan on he put WAYYYY too much silicone on the gasket and alot of it squeezed in the pan and broke free clogging up the pump pickup. that is how he spun his bearing. good luck.....sounds like you need some for a change

 

What the hell were you doing?

 

As far as oiling the LS1 that was taken care of with the swap obviously. Now there could be some clogging or the pump might not be working at its best I dont know. If it was caused my lack of oiling this would ahve had to be the case with the Firehawk it was in. As far as the tune it is from a totally different tuner and has been scanned. The tune is great the Tuner had done this exact same setup a few times in recent months and really similar many times. Im not worried about that. I just find the timing on this mishap almost unbelievable! Ill update here ina few hours when I now whats up! Thanks for all the help as always!

 

Ya, it was no problem, I removed the head, dropped the crossmember, (i believe i loosened the steering) and replaced the piston. Pretty easy.

later,

allen

 

Damn! I got to watch what I say! My guy called me about my truck and the 1st thing he said was about me talking **** about the PT Crusier! He straightend me out on the flames and gave me the facts! Its not valvetrain or anything else I kind of hoped it was. The blocks coming out!

 

I was sprayin a 150 shot through a supercharger, well it was fine it wasn't running lean or anything but lets just say don't ever let a dumbass friend wire up your nitrous kit even if they tell you that they know what they are doing. BOOM, yea it shattered the #8 piston cracked #4 piston blew up the intake, supercharger and bent the throttle plate in the tb.