What are exhaust hangers?

The exhaust system on your car is generally suspended beneath the vehicle's underside; exhaust hangers are what connect the vehicle body to the primary exhaust system.
Due to engine vibrations and the nature of an exhaust system, these need to be isolated from the vehicle.

Why do manufacturers use their chosen materials?

Exhaust hangers produced by manufacturers from the factory are designed to reduce and minimise NVH (Noise, Vibration, Harshness). In most applications, these are made from soft rubber.
Cost is a significant factor, and rubber is the most cost-effective method of producing exhaust hangers. The biggest downside to using rubber is the lifespan and resistance to harsh conditions; over time
and significant temperature changes, the rubber can harden and become brittle. Once this happens, the exhaust system is no longer correctly suspended.
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