this is what gave me the idea... but he never finished it... or gave a true write up on it... so i will...

http://www.dieselplace.com/forum/sho...d.php?t=331006

 

Really? So, I guess the engine was fully developed for GM, and not an adaptation of an earlier design.

I'd be inclined to think that the THM700R4/4L60(E) would be a bit light behind a V8 Diesel, but I've not tried it. The 4L80(E) makes more sense, since that's essentially a THM400 + OD.

If you want to try it with a THM700R4/4L60, make sure you get one made 1988 or later. The earlier THM700R4 (1987 and earlier) suffer from several flaws - and I've found (mainly through GM techs) that the only effective repair is outright replacement.

The 4L60 is the later designation for the THM700R4 (four forward speeds, longitudinal mount, I don't recall if the "60" was a shortening of the torque rating [which would then be 600 pound-feet] or a relative strength rating [60/100, or something like that.]) The later appending of the "E" indicates electronic control, which came somewhere around 1994/1995.

The THM400 became the 3L80, which lead to the 4L80 (addition of overdrive.)

I believe there is also a 5L80E - which would be the addition of a low range to the THM400 in addition to a top-end overdrive. However, I'm not about to swear to the idea - I've been wrong before (while I do hate when it happens, I'll also admit to it. After all, how else am I to learn from it?)

I really would be interested in seeing your notebook if/when you do this swap - as much for the novelty of it as for the technical aspects. Compared to the SBChevvy/BBChevvy, where does the V8-379 Diesel fall in size? I've heard of several SBC swaps into XJ/MJ, I've seen pix of one BBC swap into an XJ (it was a 454,) but this would be breaking new ground...

 

from what ive read the 700r4 was used behind the 6.2 in civilian models but it never lasted... most say the TH400 holds up great and the aftermarket world can make the TH400 a stout tranny on top of what it already is... i had one in my 70 400/400 impala and had to get it rebuilt... lost reverse and the high gear... which from what i understand is a flaw that the TH350 and TH400 share and most transmission shops make this change then whey rebuild them anyways... guess its in there "rebuild kit" t do so... cause my tranny guy said its right now and it wont happen again...

The TH400 is great for this swap i think because of the strength and its 32 spline output to mate it to the 241 transfer case... which drops the idea of needing a $500 adapter to something for driver side drop under a chevy... bolt right up and go... im not positive but i think the 4L80E is a different spline count and im not sure if theres another transfer case that will bolt to it thats driverside drop... also the E worries me... i like the idea of OD of course... who doesnt... but what computers and extra stuff would i have to worry about to get it to work? it can work... but would it be worth the trouble then just bolting in a TH400?? a 5L80E... dont know anything about that one BUT... if its got good low end like the TH400 and OD like the 4L80E then it might be worth doing the electrical to get it to work... but then we also gotta know what output spline it is and what clocking...

Its gonna take me some time to get the engine here... i cant just drop a grand.5 and it all be here... lol... my plan was to sell the tranny and motor from the jeep and buy it but as soon as i sold my tranny the DD broke down and i dropped all my money in it... but my goal is to have it driving by this time next year... if i can get my DD sold and buy another cherokee or comanche cash for a DD thatll save me a ton of money and this shouldnt be a problem... but wife wants a kid so i gotta focus on one toy... was the cherokee and CTD now im sticking the diesel in the cherokee so i get best of both worlds in one toy... lol...