Automotive clutches — vibration control in a single dry-plate clutch In a single dry-plate clutch used in vehicles, which component primarily absorbs torsional (twist) vibrations between engine and gearbox?

Introduction / Context:
A single dry-plate clutch must transmit torque smoothly while isolating the driveline from engine firing pulses and gear tooth disturbances. Understanding which element damps twist fluctuations (torsional vibrations) is crucial for diagnosing shudder, rattle, and drivetrain NVH.

Given Data / Assumptions:

• Clutch is a typical automotive single dry-plate type.
• Driven (friction) plate includes a splined hub that fits the gearbox input shaft.
• Springs may exist in two places: cushion springs under linings and torsional coil springs in the hub.

Concept / Approach:
Torsional vibrations are angular fluctuations of speed. The component that provides angular compliance and damping between engine flywheel/cover and transmission input is the set of coil springs in the driven plate hub. Cushion springs serve a different purpose: they soften axial engagement to reduce judder but do not meaningfully isolate twist.

Step-by-Step Solution:

Verification / Alternative check:
Exploded views and service manuals show the driven plate hub containing multiple coil springs and often friction shims serving as a torsional damper.

Why Other Options Are Wrong:

• Cushion springs (B): cushion axial clamp engagement; not primary torsional dampers.
• Central hub only (C): a rigid hub transmits, not absorbs, torsion.
• Clutch pedal (D) and rubber pad (E): driver interface parts; no torsional damping in the torque path.

Common Pitfalls:
Confusing engagement smoothness (axial) with torsional isolation (angular). A clutch can engage smoothly yet still transmit torsional rattle if hub springs are weak or seized.

Final Answer: