op wrote:
Should I worry about the 35 PSI maximum pressure and the 105S SL ratings?
A 35 psi P tire (passenger tire) doesn't have enough pressure to hold the tire to the wheel on your toy hauler as they side slip around corners or backing. The beads can become unseated.
Another down side of a P tire on trailers is fed regs say the tire capacity has to be derated by dividing capacity by 1.1.....example a P tire with 2375 lbs capacity now has 2159 lbs capacity. P tires work great on single axle and lighter weight tandem axle trailers
I keep P tires on one of my smaller utility trailer with 3500 lb axles but they carry a 51 psi rating.
Those Goodyear LT tires can last 8-10 years/30k-40k miles when stored and maintained properly.
I wouldn't down grade from a LT tire to any brand ST tire.