Steve,
I changed over to Michelin XZA2 Energy and installed the Koni shocks, I really love the improved ride and handling. The Coach had Good Year G70's. With the Good Year tires I felt the vibrations and ruts in the road. When I changed the tires all that went away.
After asking the same question regarding increasing the tire size here on the forum. I checked the clearance in front and for the back tires. I could up the size in back, but in the front there isn't enough clearance to go to a larger tire. The coach now runs 275x75x22.5 LRJ and I wanted to go the 295x80 tire.
When I added the shocks, the excessive bouncing, porpoising, sway, and wind drift went away too.
I purchased the tires through the FMCA Michelin Advantage program. For the shocks best price I found anywhere was at Henderson's Line up, (SuperSteer). They beat any on-line web site or store that I checked, and I check quite a few. Plus there wasn't any tax (Grants Pass, Or) and they shipped the order for free, I received them in two days.
Call John Henderson at 888-898-3281, he will know the right Koni part number for your coach. My 2000 Patriot Thunder used the same shocks as Karl. 4 shocks in front and 2 in the back. I was told some Beavers have 4 shocks in the back.
Good Luck,
Bill