I have these steer tires on my bus, every friday evening, medium rare. think Mango's on to something here.

I also agree with Gary, I do not think that steer tires are an actual tire designed for turning etc or even for the front of the bus. I do know that the use of the 365's on the front will make a difference and they do have 19/32 of tread and are 14.3" wide, a really good choice if you want better handling and more tread, see link below. The 315 80R 22.5 XZA2 are 12.5" wide and have 17/32" of tread, not quite as robust. So if you want the added tread life and width, I would highly recommend the 365 Upgrade tires from Michelin.

365 70R 22.5 specs: http://www.michelinrvtires.com/miche...o.do?tread=XZA

315 80R 22.5 specs: http://www.michelinrvtires.com/miche...=XZA2%20ENERGY