There are some rather strange handling characteristics of heavy vehicle tracking over the road, particularly those of a bus. If you envision a school bus, for example, or a semi-tractor, the driver sits behind the front wheels and the front wheels actively control the direction of the vehicle. In a Prevost coach, for example, there is a 'castering' effect, that is, the front wheels do control the direction of the vehicle, but they also follow the line of direction of the vehicle. It sets up a rather odd physics problem.

One of the ways that people have rigged up their Prevost conversions is with the use of a Howard Center Steer. These rather expensive rigs promise that if a bus blows a tire, the bus will automatically track to center and perhaps more importantly, improve steering characteristics.

I 've had some time to be thinking about some things and I think it is a bad idea to try to re-engineer Prevost coaches, particularly suspension systems and steering systems. This is the one area which Prevost has done a truly amazing job with their own parts and off-the-shelf parts and getting into the front suspension/steering system of a Prevost shell seems to me to be a pretty bad idea.

Drove a Howard equipped coach a number of months ago and it didn't seem to make much difference in handling; maybe guys are just looking to find a place to put some money.

Hmmm.