How many wheel bolt patterns are there? Are the bolt patterns based upon axle load rating? Is switching from 15" five lug to 16" five lug as simple as buying wheels and tires?
I am not aware of any 5 lug trailer wheels made for 16" tires. The common lug patterns are 5 stud 15" on the 3500 Lb axles, 6 stud 15" on the 5200 LB axles, and 8 stud 16 " on the 8000 LB axles. My 15" 6 stud 5200 LB Dexter torsion bar axles have much larger brake drums that a 3500 LB axle, I imagine the 8000 axles are even larger. I have never had any issues with wheel bearings on my 6 stud axles, but I know several guys with the 3500 LB 5 stud axles that have had wheel bearings burn up, and in at least 1 case, the damage was bad enough that he needed to purchase a new axle. Although the 8000 LB axles are really beffy, they are also a bunch heavier. A fair compromise, if ordering a new trailer, is to specify the 5000 LB 6stud axles, with 16" wheels and tires. A buddy did that on his trailer, so the trailer was built with them in mind, so they fit fine, but a downside is the tires are at least 2" taller, so that raises the trailer floor by at least that amount, which means a steeper incline on the rear door, and a more severe "breakover" angle into the dek, which can be a pain with low hanging headers and oil pans. I would think that the majority of trailer tire failures are on rigs that regularily haul very long distances, in hot weather. I know a couple of Super Stock racers who have had blowouts even with 16" LT tires, but they often tow to races over 2000 miles away, in 100+ degree summer temps, stopping only for food, fuel and bathroom breaks.
