There has actually been quite a bit of posting on this question...if I could only remember the title it was under...???
Anyhow, the big problem with the 7.3 or with a cummins or anythin like that is the weight. Serious suspension upgrades would be needed. Moreover, if you are putting a healthy diesel in there, count on upgrading transmissions, transfer case (I think...dana 300s are strong, but I don't know if they'd like living behind a healthy diesel), driveshafts, and axles. From what I remember of the last group of posts, a GM 6.2L would be the best bet...it's a diesel, but it's not as heavy, and it isn't quite as potent in stock form. Probably the simplest solution would be to find an old GM 350 diesel in an olds or something, but from what I hear, they aren't build nearly strong enough to withstand the compression from the diesel. As far as the possibility of using an Isuzu diesel, that would probably be easier...lighter, smaller, etc. Some had mentioned looking for a 4 cylinder cummins and installing that. If you go with the 6.2 and want an auto, a TH700R4 is probably your best bet...it was in a lot of diesels, and finding the two together would probably not be too hard. But you'll probably run into length issues with that setup, and might want to look into a manual (sadly, I can't remember what the manual the diesels came with). There is a really good GM diesel webpage. I'll try to find it, but it's something like 6.2diesel.com or something like that. Til then...
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