New build has less than 2k miles on it...
fought belt tensioner issues for quite a while...
resolved that and finally got it tuned...
went to pick it up from tuner, let it run for a while while chatting with tuner, had him load an "emissions tune" and e-mail me the dyno tune...
got ready to leave and noticed I had no oil pressure...like 15-20lbs @ idle in Park and 10lbs or less when put into gear...low oil pressure warning flashing.
Tuner had multiple WOT dyno runs while tuning...all w/ perfectly fine OP.
Changed oil and filter...pan and cut-open filter had copper in it.
Towed it back to shop that installed everything...hoping that new oil pump's relief valve may be stuck, I bought a new one and we dropped the pan.
Some metal in pan...rod bearings showed slight wear...thinking P series bearings needed to be replaced with H series and that we may be able to roll new ones in, I exchanged new pump for a new set of H's.
When checking clearances and about to install new rod bearings, we checked a main to be sure there was no wear there and discovered major bearing wear...even some copper transferred to the main journals.
No knocking...no audible signs of this at all...low oil pressure was first and only sign.
I noticed that the current bearings were 0.010's and remembered that the last build we polished the 0.010 crank and used P series 0.010's.
I checked the invoice from the machine shop and it listed "turn crank - $125".
Could they have possibly turned it to 0.020 and installed 0.010's?
The bearings are the only items that I didn't supply.
Three machinists, including the one I used, have looked at this and claim that from what they see that it couldn't have been that.
Journals have not been measured since the motor is still in the truck.
The only thing that makes me agree with them is the thought that it would have been making a racket from the beginning with that much excess clearance. Would it have...w/o a doubt?
I have NO clue what has caused this.
They are claiming the stock crank being the issue...which is known to be good to 1k+ hp...even with crank driven superchargers.
I'm no where near that level.
Any thoughts?
Thanks!

 

The crank wasn't turned .020 with .010 bearings and ran for 2000 miles without issue.

 

I haven't had any issues with stock cranks.

Was the crank pulley pinned? Did the pulley come loose? If it came loose, or spun, that might explain something.

Hope you get it figured out.

 

Same thing happened to my forged 6.0. Absolutely silent, only hint of damage was low oil pressure. Pulled the pan and found this:



Turned out to be excessively loose main bearing clearances.

 

Crank & pulley were keyed

 

FYI...
NO spun bearings...
Lower half bearings have the most wear...
Middle ones worse than others...
All top halves have minimal wear, in comparison...

Rotating assembly consists of stock crank, Howard rods and Diamond pistons (higher CR than last build, 9.5CR)

 

Machine shop invoice:


Main bearing:


Crank journals:

 

Thoughts thus far are:

800+ fwhp (w/crankshaft driven SC)
+
Loose converter
+
4600+ lb truck
=
Flexing crankshaft

 

If only the bottom half of the bearings were bad Then I would say its tune related.

What happens when you push to hard on the roatating assembly??? It tries to push it out the bottom of the block... That's the weakest link.


Guys like Jarrod AKA Stock48 have pushed 25 PSI through a bone stock Bottom end and making over 1000 hp, there still alive and currently running. Maybe there were some small assembly issues but I am willing to bet your tuner is partially to blame here.

EVILGMC had a similar issue and actually bent the crank. It was definitely tune related.

 

^^ Good possibility here.