I have a 98 gmc half ton 4wd with 265/75/16 on it
.Can I put 17" rims on it and what size tire would
be the same as the ones I have
Yep 17's will work just make sure the offset is the same and you would go with 265/65 or 265/60/17. It all depends on the tire overall diameter, I have noticed that there can be as much as a 1/2 an inch difference between tire companies and still be the same size.