E450 Wandering caused by too little +Caster
Here is the way I see the topic of E450 alignments:
Ford ships all E350/E450 cut aways with identical fixed, non adjustable
caster/camber sleeves, "one size fits all".
The RV builder almost never changes the Ford sleeves, as a result:
If the final RV build is nose down one degree then the runtime caster will be about +3.5 degrees. These units can have a real wandering problem.
If the final RV build is nose level then the runtime caster will be about +4.5 degrees. These units are probably indifferent.
If the final RV build is nose up one degree then the runtime caster will be about +5.5 degrees. These units are probably just fine, possibly excepting the 31 footers.
So, some RVs have a problem and some do not have a problem. JMO.
POPULAR MECHANICS MAY 1973:
If too little caster exists, the car will wander and weave,
thus necessitating constant corrections in steering.
PS: Caster is very important BUT NOT a tire wear parameter.