The keys to heavy suspension maintenance are knowing when to rebush and selecting the right bushing material.
Worn center bushings can result in increased lateral movement of the axles on turns, often well beyond the allowable 3". This causes the inside walls of tires to rub the suspension frame hangers. To avoid serious tire damage, center bushings should be replaced.
Most rubber center bushings perform well when placed in standard-duty applications. Hendrickson recommends use of rubber bushings as an economical component that requires no maintenance while providing long life in various vocations.
However, when rubber bushings appear to be wearing prematurely, Hendrickson's high-confinement rubber bushings are available. High-confinement bushings also are an option for the extended service life they provide.
For extra-heavy loads or highly severe applications, Hendrickson suggests two options: fully bonded rubber bushings or bronze bushings. While the fully bonded bushing requires use of transverse rods, it still requires no maintenance and typically results in long service life. Bronze should be the choice when vehicles are expected to encounter a large amount of tight cornering conditions. These products are more resistant to axle walkout.