Why are New Tires on Boat Trailer Evenly Worn on the Outside Edges of the Tread

Question:

New HS 188 ST boat trailer tires. 225/75D15 They are 5 ply bottom and 3 ply sidewall I have driven 1000 miles at 65 mph on these Brand new tires. Rim and trailer custom built for my boat. Looking at the tread there are 5 columns of tread which go side to side across the contact area of the tires. When I drive through sand at the ramp. I have a perfect center 3 treads with sand and the outer and inner are worn exactly the same where sand wont stick. This is exactly the same wear pattern on all 4 tires. I have always inflated to max cold 65psi before running the trailer. Theyre mounted on torsion axles. Im baffled. Can you please explain

asked by: Tony N

Expert Reply:

I spoke with our resident tire expert about the wear on your tires and the only known cause for the treads to be worn evenly on the outside edges as you described is an under-inflated tire. I know you stated that you always keep them inflated to their max psi, but I recommend verifying the maximum psi of your tire as listed on the tire sidewall. Since they are newer tires, it's possible that they have a different psi rating than the previous tires on your boat trailer.

I have also included an FAQ article on trailer tires that you may find helpful.

expert reply by: Chris R