The reason I asks is because I am going to buy a M9540. They have one on the lot with every thing I wanted on it but the air ride seat. Dealer said he could order one for it for around $900.00. I can live with that if is helps the ride some. I have a M6800 and a L5030 both with cabs. The M6800 is not to bad on the ride but the L5030 is pretty bad. The M9540 is going to have radial tires and wheel weights so I would think it would have a better ride than anything I got any way with just the stock seat. One more thing if I order the air ride, is it the whole seat and everything or is it just the base?