Sway Bars

There are 3 axis that come into play in handling.

  1. Up/Down
  2. Side to Side - yawl
  3. Roll - Sway

Now in simplistic terms:

  • Item 1 is controlled by the shocks
  • Item 2 is controlled by trac bars like UltraTrac
  • Item 3 is controlled by sway bars

But, the following will have a big influence on what you need to add and how much is added.

  1. Coach wheel base
  2. Suspension style - coil springs or leaf springs
  3. Coach weight
  4. Weight distribution
  5. Over hang - stretched chassis
  6. Tire size and pressure
  7. Roll center

One last thing that RV owners look at is steering wheel correction. A steering stabilizer provides some relief from consistent steering wheel correction. You might consider:

Does your coach have......

  • To much "Rock & Roll"?
  • Leans to much when you take a corner.
  • Wallows at low speeds on uneven roads.

Then maybe you need front and/or rear sway bars.

How does it work?

The short version is the sway bar increases the stiffness of the springs, which in turn decreases the tendency of the coach to lean or roll when cornering.

The long version... The sway bar connects the 2 wheels together just as the trac bar connects the axel to the frame. Now, when the coach starts to lean or roll the weight is shifted to one side and the sway bar pushes down. The downward force is transferred to the other wheel via the sway bar. But, because the sway bar can't move the downward force is negated by some percentage. This percentage is determined by the size (diameter) and the stiffness of the sway bar.

What determines the size of the sway bar? If we were designing a sway bar for a car we would be concerned about roll center of the front and rear axles, center gravity and size of the front bar versus the size of the rear bar. But for an RV the bars are sized to give the best reduction in roll/lean and not effect the ride.

Front Sway Bar

Rear Sway Bar

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