I have.... Any idea why this would happen?

 

You bought it like that or? so weird...

 

No, the box is from the new REPLACEMENT for the one that cratered on Cyl. 6

 

was the pushrod bent? it looks like some serious mushrooming right where it came apart. Just seems weird that it would come apart like that.

Maybe some sort of defect, who knows. I certainly can't give any reasonable input on why it did that.

 

Yes, saw that happen once, don't know why it did it, but I know my buddy bought the truck real cheap because no one bothered to pull valve covers and diagnose it.

 

valve adjusted too tight? or the valve dropped and the piston shoved it back up?

 

Appears to a bad factory weld because there is very little weld bead on the end piece. Looks like there was slight weld penetration on the end piece.
The weld, if good, should have tore metal out off the end piece when it separated.

 

Mushrooming happened after it came apart.

 

Wow, sorry about your luck.

your having alot of problems with your LOW mileage truck that most of us don't see until 500,000

Did you have to get your head gasket replaced ?

 

that's kind of what I thought but wasn't sure.

 

how good is oiling to top end looks like it saw alot of heat

 

That's from the electro-weld process when they're made....

 

I'm with him. The only other cause I can think of is running with too much lash for a long time, but I'd expect other stuff to look really beat up too.