Ive owned a 98 2wd 2.5, and sold the truck with 240k. I owned a 99 with the 3.0 and it a dog, but I did not have any problems with it. I now have a 2000 4x4 4.0, 100k and it is running strong. The mpg on my 4.0 is better then my 3.0. The body is rusted at the bottom of the doors, tailgate, front core support and the spare wheel rusted away. The Michigan roads wore down the suspension around 80k.
For 6k, find a truck outside of MI without rust. The 2001+ will have the OHC and 225hp vs my 185hp. How ever, if you did a suspension lift on rangers 1999+ there is only two companies that make the parts and it starts around 1500.00. 1998 and lower you can get everything for 600.00.
1999 and 2000 4x4 have a pulse vacuum hubs and you have to watch for air leaks, but they can be converted.