Can I put bigger tires ?

Also if you change the outside diameter of the tires, you would be changing your overall gear ratio to a lower one. Could effect performance, especially on hills. You speedometer could be off too, as it could show you going slower then actual speed you are going. Would probably need to have speedometer drive changed, or computer reprogramed.

Lastly, I would wonder it manufacturer offers a larger tire for you MH. I would think that the size tire that it came with is there for a reason. You may check recommend tire pressure manufacture requires to see if you are overinflating tires for actual load MH carries.