It's actually happening. I have a great 6.2 J-Code ready to be installed, now I'm trying to decide what the rest of the drivetrain is going to look like.

I have a well equipped machine shop and the time to do things right. My budget is limited though so I'm not planning to go too crazy.

I was planning on fabbing an adaptor plate between the 4hp22 and a chevy bell housing, and, essentially, bolting everything right up. Obviously there's more to it than that, but it's pretty basic.

The upside is I keep things mostly stock, cheap, super easy to do, and I can be driving her in no time at all. The downside is that the torque converter is ill suited to the diesel and I'll definitely loose some mpg (main reason for doing this) and power.

I know a 700R4 will bolt right up to the diesel and it's a match made in heaven. But then we run into T-case issues.
The internet makes it sound like divorcing a LT230 is somewhere in the difficulty level of preparing a frozen pizza, but when I search around I see elaborate adaptors and intricately machined parts. Am I missing something?

Also, it looks like the 700R4 pushes the t-case back a few inches and presents clearance issues with the front prop shaft. As I understand it the later model prop shafts are smaller diameter than most of the '80s models I'm seeing these be installed in, so maybe clearance isn't an issue. What about length? I'm running a 4" RTE lift, I assume the rear shaft will take up the lost length, but the front will have to be lengthened probably. So many things to think about!

Lastly, I've heard the early 3speed RRC's had a higher hi range ratio, so if I can find those hi gears and a torque converter from a 4.6 (it's my understanding that they stall at a lower speed than the 4.0) maybe the ZF box would work fine.

 

If you use a 700 r4 be sure it is newer then 1989 early ones had problems, also their shift is controlled by the detent cable so keep that in mind where as the turbo 350 and 400 are vacume but you lose fuel economy without overdrive ,

I am of course talking non computer trannys

Never done a diesel swap so can't help there

 

Thanks, I'll only consider the later models then.

I'm also thinking maybe a NV4500? They're only 12" long, half that of the autos. So I could divorce the t-case, leaving it's position the same so no propshaft mods and fab a short driveshaft from the output of the tranny to the input of the t-case? Any reason that wouldn't work?