Updated January 11, 2011.

The Hitch Torsion Bar Story

Load equalizing hitch or torsion bars, are designed to transfer travel trailer tongue weight, back to the trailer axle or axles, as well as transferring some of the trunk weight or rear end weight of the tow vehicle, to the front axle of the tow vehicle.

Typically, 60 percent of the tongue weight goes to the tow vehicle and 40 percent goes back to the trailer axle or axles, with proper rating, properly installed and properly adjusted torsion bars.

Torsion bars have different ratings so that they can properly match the tongue weight to a specific tow vehicle. Generally, the heavier duty the tow vehicle, the lighter duty the bars should be, so that a soft ride can be provided for the Airstream.

Different rating bars should be used for different types of tow vehicles, for the same trailer tongue weight.

Heavier duty bars along with heavy duty tow vehicle transfers considerably more road shock to the front of the trailer.

That can and often does, cause a variety of damage to the trailer as well as opening closet doors, throwing clothes off hangers, opening drawers and generally rearranges whatever might be inside the trailer.It also often causes fatigue cracks in the frame, and sheet metal, causes rear end separation, wears out the entrance door hinges, shearing of rivets and creating water leaks.

There are several different types of hitch torsion bars available, in different ratings and shapes. There are square, round andtapered bars.

We tested bars made by Reese, Eazlift and Equalizer. We also tested different shape bars.

A hitch box receiver was used that could not move. We inserted the different ball mounts to match the respective torsion bars.

A sensitive scale was used, that had a chisel point edge, and was placed underneath the bars, all at the same distance from the pivot point at the ball mount, and was lifted by a floor jack to increase the stress on the torsion bars.


Round bars DO NOT offer any significant difference in stiffness or softness from the tapered bars.

Reese dual cam sway controls unequally increases the bend in the torsion bars when a turn is made, further increasing the torsion, which advances the sway control to return the rig to a straight line. True friction type sway controls, offer resistance when turning and the same resistance returning to a straight line.

The Equalizer bars offered the least bend for a given weight, making it the stiffest torsion bar tested. That in turn, transfers the most road shock of all the torsion bars tested.

Andy Rogozinski
Inland RV, Inc.

January 10, 2011

NOTE: Information from sources deemed reliable have been used in this Article.

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