Straight axle front ends

It is true that air bags cost a little more than Sumo springs but Sumo springs are not adjustable. Having the ability to pump up the air and stabilize the coach in heavy winds is worth the extra cost to me. I had Sumo springs on one coach and they did prevent the jarring bottoming out but most of the time I want the ride to be stable when I am driving and am not too concerned about what happens when I hit a pot hole. With the air bags I can adjust the ride as the winds and the road conditions dictate. On a smooth road, the pressure is low for a nice smooth ride. On a rough road, or high winds, and the higher pressure prevents the excessive sway and bottoming out of the suspension.