Funny you should mention that.
A couple yrs ago I had a loaner coach from SETRA that rode so bad I parked it and told them to bring me another.
(this was after hauling a load of farmers to a CO-OP sponsored event and they told me they had tractors that rode better than the bus did.)
Several even told me they could make it ride better. When I asked how they told me to "start driving it in fields!"
SO Setra had me take it to a tire dealer that could balance the tires on it.
Which I did I took it to Best One Tire in Paducah and Setra paid them to take all the wheels off and balance them.
After that it rode somewhat better, but still rough.
Setra didn't think Best One did a good job balancing them and had me take it to another place where they tried to balance them and told me that some of them were so out of round balancing wasn't the problem or cure.
Setra told them and me we were crazy all it needed was balanced.
Well I parked it and only used it after the last of the 2 80's model MCI 96A3's we had then had left the yard.
When Setra finished our bus we took it back to them and I had the main guy over customer service got for a ride with me in it.
He immediately agreed it was terrible and told the service manager "I don't care what it is have it fixed TODAY, our reputation as well as our customers are being damaged by it!"
Well they tried telling me their local tire shop balanced them. But several weeks later when I was back over there I looked @ it and it had 8 new Firestones and I did not see one weight anywhere on the outside of a rim!
I now have all my tires done @ Best One in Jackson, TN and they inflate them laying on the ground lying flat and if it doesn't balance after the second time they call another tire up from the warehouse and send that one back. I watched 'm send back 3 out of 8 one day! But when I hit the rode that bus rode better than ever! (they have there own warehouse next door)
It cost me $150 or more per tire than it used to when I was buying my Kumho's directly from the tire warehouse in KY and having my local guy install them, but hauling people the ride is worth it.