Alright guys, I've got a 2004 Ram 2500 that has a severe rod knock. I picked up a 2006 engine out of a car (I believe it was charger) for dirt cheap. My plan is to use the bottom end from the car engine and swap my top end on to it. I'm looking to see if there's any info you guys have for me about non interworking components or differences between the two engines that I need to be aware of. I've done some research and it looks like MDS may be an issue, but I can solve that with a block off kit.
Anything else that I should be aware of?

All knowledge is good.

 

I haven't seen this done before so I can't provide any experience on your project. I recommend you contact the manufacturer of the parts you are exchanging and see if they can give you insight. I think Melling and Mahle makes internal parts for both engines.
Do you know the condition of the donor hemi?
Can you tell us why you want to do all of this work for a spun bearing? Do you plan on replacing crank bearings? Seems easier to just replace the bearings if you're going to be in there anyway. You may need to grind the crank journals, but there are kits for that. I think you know this already, just asking to see if there is additional info that may help us understand more about your engines.

 

I bought the truck as is, with the rod knock. The previous owner continued to drive the vehicle after the rod started knocking. He continued to drive it for months... Daily. The damage could be quite bad... He couldn't believe it hadn't let go yet. He was planning on driving until it exploded, but somewhere along the line he started to feel bad. The replacement engine from the car was dirt cheap... $300. It's high miles, over 200k, I'm told. However, it had no issues. Also, the guy got the truck from had put new heads on it about 50k miles ago. And yes, I'm planning on putting new rings and bearings in the engine before install. Hopefully my reasoning is making more sense to you now.

 

If you're gonna strip it down to he short block then you'll be fine, just make sure you swap cam AND lifters to non-MDS stuff. Then you can pull the solenoids and use the block plugs. Technically you only need to pull the lifters on 1, 4, 6 & 7 but it's a good idea to replace them all with a different cam. You'll need to reuse everything else from your engine except cylinder heads; use the set in the best shape (both have EGR). Also includes your front timing cover and intake manifold as well as dipstick (car version id on the wrong side). Will also most likely need to swap over the sensors; there WILL be harness differences (CAN bus vs PCI bus). Will need to swap flex plates, make sure there isn't a pilot bearing in the back of the crank. NAG1 & 545RFE are very different transmissions and the way they interface with the same engine is different. Take a good long hard look at your oil pan. Probably worth it to spring for a new one as they tend to rot under there being stamped steel vs cast aluminum like the cars (no you can't use the car pan). If this were my project I'd cam it, but if going for stock I'd get a newer/better oil pump and a factory 6.1 timing set w/tensioner. Head bolts are TTY so you'll need to replace those as well as the crank and cam bolts.

 

Magnoom, thank you so much for the information! That's exactly what I've been looking for. The only thing I have a question about is the 6.1 timing chain... How does that differ?
Also, I had someone tell me that the car/truck engine mounts are different and there's a motor mount boss in the car blocks that isn't drilled or tapped that needs to be for the truck style engine mounts... Know anything about that? I haven't been able to find any info on it.

 

Stronger tensioner, better chain. 6.1 is a performance engine, 5.7 is not. Ye olde recipe for a cam swap in the early 3G hemi days included the 6.1 timing chain and oil pump. Longevity.
From what I've seen people post about the mounts it's hit or miss; some people have run into that problem and more have not. There doesn't seem to be any rhyme or reason to it.

 

Awesome!
Thanks again Magnoom for all the great info!