Class C steering response
Recently purchased a 30 ft. 2003 Itasca Spirit with the Ford V-10. 1st experience with a motorhome. Used to towing a small 5th wheel with a half-ton Chevy. One thing I don't like is that the Itasca's ...
Forum Discussion
J-NS,
You've gotten great advice. There's NO shortage of E-Series Handling threads here. Couple comments:
Donn - A Good Alignment Shop will check and adjust all the primary angles which are Caster, Camber, and Toe. That shop will understand that proper alignment could call for "offset" bushings at the Upper Ball Joints. This makes E-Series alignment trickier and more labor-intensive (and therefore more expensive) than on a big straight-axle dump truck or road tractor.
Harvard - He's self-taught in alignment and has figured out what works. Setting Caster to Mid-Range (which most shops will try to do) is NOT something that works. As he pointed out, you want Caster on the High-Positive end of its range. Caster and Camber are both set at those upper ball joints. Caster is more important to us, but you don't want a totally wacked out Camber either.
Myself - I found that both C's we've had (both on Ford) experienced vague steering and wandering on the road until I got the Toe from Out (negative) to slightly IN (positive). The spec is Zero or Straight Ahead.
Another factor - Weight and Tire Pressure. Take it to a truck scale. If you can, get a weight for each corner, but you can work with Front and Rear Axle weights. We all know that excess tire pressure makes for harder ride, but excess FRONT tire pressure makes for instability in steering and tracking. HINT: You shouldn't ever need more than 65PSI and possibly much less in the Front Tires.
Front Axle Loading vs Rear - Your truck scale ticket will help here. There are two common suggestions. 1. Front Axle should be at least 75% loaded. 2. At least 1/3 of the total scale weight should be on the front axle. They work out to about the same thing. If your coach's wheelbase isn't long enough, that can be hard to achieve. We had an OP with about 27% on the front axle and could never get it to track on the road. Traded it/Sold it, I forget which.
So - What is the Wheelbase of your RV?
You've gotten great advice. There's NO shortage of E-Series Handling threads here. Couple comments:
Donn - A Good Alignment Shop will check and adjust all the primary angles which are Caster, Camber, and Toe. That shop will understand that proper alignment could call for "offset" bushings at the Upper Ball Joints. This makes E-Series alignment trickier and more labor-intensive (and therefore more expensive) than on a big straight-axle dump truck or road tractor.
Harvard - He's self-taught in alignment and has figured out what works. Setting Caster to Mid-Range (which most shops will try to do) is NOT something that works. As he pointed out, you want Caster on the High-Positive end of its range. Caster and Camber are both set at those upper ball joints. Caster is more important to us, but you don't want a totally wacked out Camber either.
Myself - I found that both C's we've had (both on Ford) experienced vague steering and wandering on the road until I got the Toe from Out (negative) to slightly IN (positive). The spec is Zero or Straight Ahead.
Another factor - Weight and Tire Pressure. Take it to a truck scale. If you can, get a weight for each corner, but you can work with Front and Rear Axle weights. We all know that excess tire pressure makes for harder ride, but excess FRONT tire pressure makes for instability in steering and tracking. HINT: You shouldn't ever need more than 65PSI and possibly much less in the Front Tires.
Front Axle Loading vs Rear - Your truck scale ticket will help here. There are two common suggestions. 1. Front Axle should be at least 75% loaded. 2. At least 1/3 of the total scale weight should be on the front axle. They work out to about the same thing. If your coach's wheelbase isn't long enough, that can be hard to achieve. We had an OP with about 27% on the front axle and could never get it to track on the road. Traded it/Sold it, I forget which.
So - What is the Wheelbase of your RV?
