[Richard]

Thank you all for the comments.

I do agree that toe in has a huge effect.

I wonder how much effect sitting in front of the front wheels has versus sitting behind them in terms of the seat of the pants reaction to steering movement. Anything in front of the wheels is going to move further for a given steering input than anything behind the wheels. That's the reason we learn not to over steer.

I also wonder if the airspring suspension in front contributes to the vague steering. The straight axle coaches have a panhard bar to keep the coach from moving side to side over the air bags and the IFS coaches don't need one, but relative to steering stability I can't tell any difference between the straight axle and the IFS.

It does make me jones for a drive in one of the toterhome style rigs like a Renegade built on a Class 8 chassis.