All Ford Ranger, Mercury and Lincoln Aviator SUV wheels have the same
bolt pattern. You can do this but I would not go larger unless you have
a 3:73 gear in your truck. The taller 17" wheels will hurt your mileage
and kill your pulling power unless you have the 3:73 gears. If you do
swap have a Ford dealer go through the OBD II port and change the tire
size so your speedometer will read correct. Your 98 has a electronic
speedometer and changes can be made through the OBD II port. Go to Tire
Rack and look at a set of 245-70 15 tires with the 5 spoke chrome
wheels. You can purchase these new for the price of used on e-bay,
unless the used set are take-offs that no one wants. No changes are
needed with new 15" wheels.

Ron