I am suggesting it's possible the converter is balloning (heat) for some reason,something to look at.If it were me i might pull the engine pan and pull the thrust out and have a look,if there is no other damage (crank)then install a new one and keep a close eye on it to see if it wears fast.If you let it go you will snap the timing chain.What do you have for a trans cooler? How many miles on the radiator?

 

l-eater...you have a built 6.0 correct, just out of curiosity what does built mean? forged internals? new bearings?

 

Gonzo-I have a B and M cooler and the radiator has around 30,000 on it. I flush the cooler lines any time I have the system open. Slow-"Built" has different meanings to different people but here goes my list:

New block from GM finish-honed to fit the pistons
Custom Diamond dished blower pistons
Custom Total Seal gapless rings specifically built for my application (file to fit)
ARP bolts throughout
Low mileage crank turned 10/10 entire rot. assembly balanced
Federal Mogul bearings
Ported oil pump
Billet double row timing chain
LS6 cam/comp springs
Ported stage 2 TEA heads
All clearances were set to "perfect" specs

Probably forgetting something, but it was not just a factory motor-it was hand assembled and everything was right.

 

thanks for the info...i was just curious how far others who had "built" motors were going. i'm very sorry to hear about your misfortune with your setup. and i hope you get it fixed soon and get some new quicker ET's. sounds like it was a pretty solid setup before it broke.

 

Update: Pulled the pan last night and checked the thrust bearing. The crank is ruined and the bearing looks like it has been pressed against a grinding wheel continuosly for a long while. I really don't have the time to build another motor right now so I am going to look at a 6 liter at a local salvage yard today. If I can get a decent motor I'll run it for now til I get some free time and decide for sure what I want to do. I am leaning toward a stroker setup, but I know that would also dictate a 4l80 swap.