Anyone add rollers to thier Trailer

[RMccord]

I have the 335RLSB trailer. It is 35' 5" long. Have any of you added rollers to the back end of your trailers frame to help when going over a dip or from a parking lot etc where there is a grade getting onto the street steep enough where you trailer could bottom out?
If so which ones did you choose and were they welded on or clamped on?
I don't think adding them to the rear bumper would help do you? Probably just cause it to bottom out sooner and the weight would probably just bend the bumper.
Has anyone had any issues with thier coach's length and it bottoming out. I haven't just looking ahead at potenial situations. I see alot of drives and other type entrances and exits at gas stations etc that have a pretty good incline coming in or going out.
Thaks