Well, when i was looking for another truck, I had my Dad out driving all sorts of rigs. 97+ 4runner, Nissan X-Terra, and 80 Series LC's and Lexus'. I didn't have the luxury of the Diesel option either so that was a non factor. My Dad did a bunch of research and found that the fuel issue among the X-terra, 4runner and the LC's was negligable. They all were within a 2MPG +/-. For the space provided and the uses I wanted the LC/Lexus was it. However, if it were going to be used as a driver/ tow rig, I think it would be a wash between the L.C. and the 4runner. The LC's also have 3 row seating which could be a decision factor as well. Dad preferred the LC/LX over the others WRT space, power, and mileage.
I don't know about the diesels and their transmissions WRT to towing. I know Steve blew his while towing a boat and there was an issue with the torque converter.
I have towed a 16ft Double Eagle loaded with gear to Renfrew with the Lexus and with a 2000 4runner. They both handled it with no issues. I did like the heavier Lexus though, as it seemed to counter any squirreliness of the boat.
I think the diesel would be ideal if the tranny were built for towing. The 4runner is a great truck and is quite capable and mod-able (I have some Lexus front coils that work perfectly in the back for about 3" of lift

). And, of course, the gas LC is big powerful and proven.
I think you could get a '97 gas LC for the same price as a '97+ 4runner.