What type of materials are commonly used to make suspension bushings?

Suspension bushings are critical components in a vehicle's suspension system, designed to cushion and reduce friction between metal parts, thus allowing for smooth operation. The typical materials used to make these bushings include rubber, polyurethane, and various composite materials.

Rubber is often the traditional choice due to its good vibration-damping properties, which help absorb shocks and provide a comfortable ride. Polyurethane, on the other hand, offers increased durability and resistance to wear compared to rubber, making it suitable for performance applications where enhanced handling is required. Composite materials may also be utilized for their strength and versatility in different driving conditions.

The materials listed in the other options—like steel, aluminum, plastic, wood, fiberglass, and ceramic—are not primarily used for suspension bushings. Steel and aluminum may be used in other suspension components due to their strength but do not provide the necessary damping characteristics required for bushings. Plastic and wood do not exhibit the requisite resilience and flexibility needed to absorb vibrations effectively. Similarly, fiberglass and ceramic would fail in performing the cushioning and noise-dampening functions that are critical in a suspension setting. This makes rubber, polyurethane, and composite materials the ideal choices for suspension bushings.