Prostar ride and handling

Does it feel bouncing sort of like dribbling a basket ball , had that on a new T600 KW years back , found that the air bags were over inflated as well as the tires

 

The wind noise is easily taken care of. Any hardware store and get some 1/2 inch (or less) insulation, install over the window-door seal.

You're right, that suspension is a big problem. A strong cross wind can set off the stability warning.

 

I drive a Prostar and they go sway on rough roads. I just keep the steering wheel steady and the rear tandems come back under. Mine has never set off stability control though.

 

I would take it into a dealer and have it checked out while under warranty. Air bags, shocks, linkages, bushings, tires, rims, all of it. There is no saying something was missed at the factory, it happens. Is this a company truck or your own? Climb into a different one, hook up to the same load and drive a few miles and see if it's different.

 

I would suspect the suspension height is either too high or too low. With tractor bobtail, look at the torque rods that connect the rear diffs to the frame. In a tandem axle, each diff is attached to different frame rails. Those should be fairly level. Obviously, the ends on the diffs travel in an arc when the suspension travels vertically, so if they can't go "both ways" to cancel each other out, you get a sideways motion that is too severe, creating a problem. Improper shocks, that let the suspension "over-travel" will also create this problem. You might also check the 3 axle alignment --- just because it's new doesn't mean it's correctly aligned.