Hi, had my camper a short time and had a blowout. Went to Pep Boys and bought 2 new ones and put them on. Tires say max psi 50lbs. Every couple of weeks when we've gone out I check pressure and they are down to 41-42-44lbs. So I go and refill and a week later down again. I go back to Pep Boys they check them out in water tank and see no leaks. They took them off rims and resealed, will see what happens. Then they tell me should have sticker on camper that should say what pressure should be. It says 65lbs cold rim. Now I'm more confused, did I buy wrong tires? Am I ok with what I have? Any info greatly appreciated, need to be safe.