Trailer Tire Load Range

I bought a new boat July 2020. Use it 3-4 times a month but only travel 20-30 miles each way to the lake. Tandem axle trailer, I noticed that the outside edge of the tires are really worn with the exception of the back left tire (it’s in great shape) Any ideas? They are 205-75-R14 load range C. Do I need a load range D or E to keep them from getting chewed up so quickly?

Sounds like their under inflated.

The tire calls for 50 PSI, I check them regularly and they hardly ever fall below 45 lbs, I try my best to keep them at 50. My old boat I kept about the same PSI and never had that kind of wear. The new boat is about 1,500 lbs heavier though.

My tires were wearing weird, front left and rear right had a little chopping. I measured and found the front axle to be 3/4” forward on the left. Once I corrected that I then upgraded to D range tires and 20,000 miles the tires look like I just put them on. YouTube how to measure your axles.

Most load range c tires in that size are rated for around 1760# at 50psi. So, on a tandem axle trailer that's 7040#. You didn't say what boat you're pulling but to be over it's got to be a big one. Outer wear on the thread is an indicator of under inflation. Maybe try a different tire pressure gauge.

I’ll get a new gauge. Thanks for the suggestions.

I had a slime gauge that I tested. It was reading 8lbs high at 40lbs. I took it to Auto Zone and exchanged it. Replacement is more accurate.