Is it just the crank that has to be replaced? Or the rods... both? Anyone know if their's more to it? Has anyone ever done this? I still have lots of bolt on to get, but it doesn't hurt to think ahead, and hell, I'm just plain interested.

 

Did I find something that no one has an answer to?

 

Dont quote me on this but besides bore i think the engines are identical, I have never seen 4.8 or 5.3 specific aftermarket parts, they are pretty much universal. Are you talkin about swappin the long blocks or internal parts?

 

The internal parts. I think the bottom end is the only difference, but I'm not sure exactly. Was hoping to get some clarification.

 

I think it is just the crank. If I think about it I'll check when I get home.

 

The crank and the pistons are different, that about it.

 

http://www.mortec.com/borstrok.htm

According to this the pin height in the piston has to be the same because the math checks out on the difference in rod length(difference in stroke divided by 2). Since a 4.8 & a 5.3 have the same head they would have to have a different piston to keep comperable compression. If they had the same piston, the 5.3 would yeild more comp. due to more displacement compressing into the same quench area. They both have 9.5:1. So I would say, they have a different crank, rods, and pistons.

 

i think the 5.3 and 4.8 have same crank different bore and the 6.0 has a different crank with the same bore as 5.3. not certain though.

 

i believe it's just the crank and rods. as far as i know the pistons are interchangable.

 

Ok, according to the link mjhoward put up, the 4.8 and 5.3 share the same bore, and the 5.3 and 6.0 share the same stroke. Sorry to state the obvious, just trying to sort this out in my head. Well, I guess that says to me that the 4.8 and 5.3 could possibly share the same pistons, but either the crank, and/or the connecting rods are different. Probably the only way to know for sure would be to get part #s for the pistons, rods, and crank from the dealership, and see which ones are different. Keep the opinions comming though!