I bought this truck from a dealer with 98k miles. It had a very slight know, which the dealer said was the tensor pulley. After purchasing and changing the oil, I was driving and it shut off completely. Towed home. Next day when I turned on the truck it had a very loud knocking noise. After reading all the forum posts, I'd like to know if I should start by cleaning out the oil pan and all the parts inside, or should i concentrate on the rods?
I want to avoid buying a new motor if possible, the truck does turn on, it just rattles like a very loud lawnmower about to fall apart.

 

I had a Toyota that sounded simular, mine was a broken piston skirt. Sounded almost like a rod knock.

What did the oil look like when you drained it?
What filter did you use?
How long has it been since you purchased this truck, can the dealer help you out?
Do you actualy have oil pressure when you start it?

 

I suggest taking the filter off and cutting it open and seeing if you can find anything in there that doesn't belong. I have a 2003 4.6 that did something pretty similar, oil guage started bouncing and before I could pull over it shut itself off. Trailered it to shop, and mechanic cut the filter up and drained the oil and found debris. Mechanic said the timing chains ran dry b/c oil pickup was so gunked up and they chewed up the tensioners which created even more of the same problem. Mechanic said it was really gunked up inside and it was my fault for using private label cheap oil for a couple of years. I thought that oil was oil regardless of brand. I got 2 new chains, an oil pump, and the bottom half of my motor degunked and he got a whole lot of my money. It's now 65000 miles later so all in all it wasn't a disaster.