Suspension bushings: why they wear out and how to make them last

Wherever a suspension arm, rod or link meets the car body, there is a bushing: a rubber sleeve pressed into a metal ring. It lets the part pivot smoothly, stops metal from touching metal and filters out road noise. A typical car has dozens of them.

What wears bushings out

• Constant movement: every bump twists and squeezes the rubber.
• Heat and sunlight: ultraviolet light and high temperatures make rubber hard and brittle.
• Oil and fuel: leaks from the engine or steering make rubber swell and soften.
• Road salt, dust and sand: they get between rubber and metal and grind both.
• Heavy loads: an overloaded pickup or van presses bushings far beyond their normal range.

Early signs of a worn bushing

Worn bushings rarely fail suddenly. Instead the car slowly feels "looser": more noise from the road, a squeak or creak over bumps, a vague steering feel and tyres that start wearing unevenly. On inspection, the rubber shows cracks, gaps between rubber and metal, or the inner sleeve sits off-centre.

Rubber quality makes the difference

Not all bushings are the same. Good bushings use a rubber compound designed to stay elastic in heat and cold, and the rubber is firmly bonded to the metal so it cannot slip. Cheap rubber can look fine on the shelf but cracks within a season, especially in hot climates.

Habits that make bushings last longer

• Slow down for speed bumps and potholes.
• Do not overload the vehicle beyond its rated capacity.
• Fix oil and power-steering leaks quickly.
• Rinse mud, salt and sand from the underside now and then.
• Tighten suspension bolts with the car standing on its wheels, so the bushing rests in its neutral position.

The last point is one many people miss. If bolts are tightened while the car is lifted and the wheels hang down, the bushing is twisted all the time once the car is back on the ground, and it will tear early.

Replace the arm or only the bushing?

Pressing a new bushing into an old arm needs special tools, and the arm itself may be worn or corroded. In most cases a complete new arm with fresh bushings is faster to fit and gives a more reliable result.