What exactly is the car’s suspension system or is it a bouncer?

Tyres

Tyres inflated too hard will lose grip and wear unevenly, and also work like a jackhammer on everything else.

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We glibly refer to a car’s “suspension” system, often without a precise idea of what is, and what is not, a part of it.  Please clarify. --Bouncer

Lexicologists are not car buffs.  

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Note: The results are not exact but very close to the actual.