Both trucks are 4 wheel drive. I haven't gone to look at either truck yet, just seen pics and and emailed the owners, so far. The biggest thing I've seen so far is on the 79 3/4 ton is when looking from the back, the left side of the bed looks like it sits higher than the right side when you compare to the window. Also with the 78 1/2 ton he says it has a "new 350 never started needs couple things to run nothing major needs somone with time" so that could be a little iffy.