My Dad has a 93 F250 4x4. He has 16.5" wheels with 39.5" TSL Super Swampers. He keeps getting reemed on tires and they wear out fast. He is just looking for a big street tire in a 39.5" or 40" size. He is strictly wanting long lasting, he does not really off road it. If he went with any smaller tires, the truck would look a little funny cause of how big it is. Here is a pic...any suggestions are greatly appreciated.

 

He will probably have to go to a different wheel size, but a quality all terrian radial would be his best bet. THe Nitto Terra Grappler, Toyo Open Country AT, Pro Comp Xtreme AT and Mickey THompson Baja Radial ATZ are all available in large sizes, but most are made for larger wheels.

 

Toyo's Open Country would be great on your truck but they are hard to find (on backorder atm). They are not impossible to find so keep your eye out. There are many tires that fit a 16.5" wheel but they're usually aggressive MT's (Iroks, Boggers, Ground Hawgs, TSL's, etc), it's a common offroad wheel (usually the biggest out there for serious mudders). Boggers don't come in anything more than a 16.5" wheel as well as a couple other tires. The Wrangler comes in a 40" tire but I think it's only for a 17" wheel. You also have the ProComp Xterrains, but not sure if they come in 16.5, but they do come in 40's. Hope you find what you're looking for. Might want to take a look at Nitto Terra Grapplers (might come in 40's).

Truck looks sick btw, anymore pics and/or video's of it?