Now that I have come to the conclusion that I'm getting a 03 DII, how hard would it be to put a 4.0 out of a 97 into it???

The only reason I ask is because I know where I can get a complete drive line from a 97. I would start by swapping the t-case in for the CDL. But how hard of a swap would the 4.0L if the 4.6L oil pump does go???

 

Will not work.
The DI and DII use 2 completely different engine management systems.
The DI system is very basic and has default settings, so if a sensor fails the ECU goes into "default" mode, the truck runs like crap but it gets you home.

The DII uses a very complicated engine management system, if one sensor fails you are dead in the water.


They are the exact same engine, the 4.0 and the 4.6, same block and heads, just different guts and computer.

 

How hard would it be to include the engine management system in the swap???

 

Assuming that they didn't change anything important, like not drilling or threading a bolt hole here or there, it would be like installing a rebuilt long block. Strip down the replacement motor to the block and heads, swap everything thing else from the original to it. I have NO IDEA if this is possible, but I'd be willing to try it if my 4.6 blows up.

One thing I've noticed also is that the 4.0 and 4.6 appear to have the same size bore. It looks like the extra displacement is from a longer stroke. This would make me ask the question, if you crack a block, can you use any 4.0 or 4.6 block to replace it? Just rebuild it with a 4.6 crank?

 

Very hard.
The transmission is a DII is electronic, meaning it is controlled by a computer, the DI trans is old school, all mechanical.
The DII engine computer and trans computer talk to one another.
The DI engine computer does not care if you rip out the auto box and install a 5-speed.
The DII engine has more sensors than the DI engine.
The DI engine with electronic ignition is 2 steps away from being carbruated.
The DI engine with a distributor is 1 step away from having a carb.

If you were to use a DI engine you would also need the DI engine computer.(General Engine Management System)
And if you did that your trans computer would not know what to do.
So it would be very very hard to do.
The DII engine uses a BOSCH system from BMW, this increased horse power in the DII 4.0 to 188, up from the DI's 182.
The 4.6 has 200 horse power.

 

I was thinking more along the line of removing the entire 4.6 motor,trans and management system and replacing with a 4.0 motor,trans and management system. not swapping parts. but would be nice to know if they are mix and matchable!!!

 

Yes the 4.0 and 4.6 are the exact same block and heads, the only difference is the guts.
Different stroke, so different crank and cam.
I am not sure if they increase the stroke with the crank or with the connecting rods.
But either way, yes, you can buy a BOSCH 4.0 block and rebuild it with 4.6 parts and have a 4.6.
HOWEVER without the 4.6 computer you have done nothing other than rebuild a 4.0.
It is very common to install a used DII 4.0 into a '03-'04 when the engine blows up because it is a direct drop in.
Also keep in mind that you can buy a P-38 4.6 from a wrecked Range Rover or a Range Rover that is in very vary bad shape.
The P-38 also uses the BOSCH system.

 

The DII uses a entirely different trans, wont work.

 

Is the DII engine harness a standalone harness or does it tie into other thing in the truck??? I guess I should have stated in the first post that I could have the complete donor truck not just the driveline.

 

Is the harness a standalone?
I have no idea.

If you are going to worry about the reliability of the DII why not just get a DI?