Like the rest, I'd LOVE to have a diesel in my '99 Jeep Cherokee. With normal maintenance we get about 250,000 miles out of the old inline 4.0 six bangers. It seems they have started to become a bit of a collector item in these parts. I was going to sell mine until I looked one FleaBay and saw how much people were getting for ones far, far worse than mine. Mine has always been stored inside and I bought it from an old buddy who bought it new for his wife. Based on the cost of a new small/mid-sized SUV, I think I'll spend several thousand on mine and just sort of make it new again.
I already have a mild 4" suspension lift, Smittybuilt bumpers on each end and rocker panel protectors along with a 12,000 winch mounted on the front and my spare moved on top of the luggage rack (which gives quite a bit more storage room in the back). I put a locker in the rear axle and a limited slip up front and for someone who has done tons of off roading, I have been impressed where ole Red will go. Although I doubt I can find any legal way to do so, I have a super nice Cummins 5.9 diesel with twin turbos I'd love to drop in! Physically it will work. I just think our EPA rules won't ever let that fly.
Oh, the transmixers can be rebuilt rather easily and made to be relatively bullet-proof. Over here, at least for now, used parts are a dime a dozen. That will likely change over time, but I'm thinking that if I can find the right shop I can get all of the luxury items I want added to my old Jeep and have less than half of what a new one would cost me.