Originally Posted By: motor_oil_madman
I think I have them at 35psi. The max is like 50psi, but I don't have much weight on the trailer and they already have a little less tread in the middle than the outer edge or the tire. They don't look close to being low at all, but at 50psi I didn't want everything bouncing around like crazy.
Ideally on a trailer you should have two pressure numbers you stick to. When empty they won't heat nearly as much as when loaded, plus you don't need the pressure in the first place. I have carried an air tank for about 30 years and can't even begin to tell you how many times I've used it, but they are inexpensive and can be found at places like Harbor Freight, Fleet Farm, Northern Tool, or here in Canada, Princess Auto
I've replaced the pressure gauge twice on mine, plus almost as soon as I bought it I replaced the pressure hose. Just about every town has a place that caters to Hydraulic Hose users, they will build you whatever you want with quality hose and proper fittings (no hose clamps or other cheezy fitments). Don't be afraid to make it long enough for your use, the one that comes with your tank won't be much to brag about. It's not expensive, I think I paid like $9 for mine ( 10 foot hose + air chuck).
In any case they hold perhaps 10 gallons at 100~125 PSI, which is enough to fill a tire from empty, top up 4 tires, or even run an air tool briefly, which might be enough on the road to get you moving again. A $5 tire plug kit and that tank and chances are you won't get stranded anywhere, for any reason.
Anyway, back on topic, carrying that tank will allow you to tailor the pressure to an empty or loaded trailer, with corresponding lower tire wear under all the conditions you will run the trailer under. Of course reducing pressure is not an issue, so you are set either way.