Coach tends to wander

I appreciate all the help and food for thought. Tires are a year and a half old, I check pressure before each trip to be sure they have the psi the coach recommends, haven't had each corner weighed but don't carry hardly anything in the coach but know that doesn't mean everything is good, coach has 50,000 on it, have had new bushing etc. replaced in front but have not had it aligned nor have I had air bag pressure checked. This is my first MH so I guess I am learning as I go. I do have a mechanical head on my shoulders but some things I need to hear from others that have experience.
Thanks everyone for help
Jack