Power flow in a manual transmission driveline Select the correct sequence of power flow from the engine to the wheels in a conventional front-engine, rear-wheel-drive vehicle with a manual gearbox and differential.

Introduction / Context:
Understanding the power path through a vehicle's driveline is fundamental for diagnosing faults, optimizing performance, and appreciating how gears multiply torque. In a typical manual transmission with a rear differential, power flows through specific shafts and gear pairs before reaching the wheels.

Given Data / Assumptions:

• Clutch is between engine flywheel and gearbox input.
• Gearbox uses an input shaft driving a countershaft (layshaft), which then drives the main/output shaft through selected gear pairs.
• Final driven gear refers to the ring gear in the differential that drives the axle shafts (driveshafts/half-shafts).

Concept / Approach:
The engine sends torque to the clutch; when engaged, torque enters the gearbox input and is transferred to the countershaft. The selected gear on the mainshaft meshes with the countershaft gear, delivering torque to the output. The propeller shaft transmits torque to the differential, where the final driven (ring) gear turns the differential case and, via side gears, the driveshafts to the wheels.

Step-by-Step Solution:
Engine → clutch → gearbox input (drives countershaft).Countershaft → selected gear mesh → mainshaft (output).Mainshaft → final drive (ring gear) in differential.Ring gear → half-shafts (driveshafts) → wheels.

Verification / Alternative check:
Workshop manuals depict the countershaft driven continuously by the input, while the mainshaft is powered through engaged gears, confirming the chosen sequence.

Why Other Options Are Wrong:
(a) puts driveshafts before the clutch—a physical impossibility.

(b) swaps the order of countershaft and mainshaft relative to the clutch.

(d) places the clutch after gearbox shafts.

(e) includes a torque converter (automatic transmission), not applicable here.

Common Pitfalls:
Confusing terminology: some texts call the gearbox input the main/input shaft and the output the mainshaft; the functional order still places countershaft before output.

Final Answer:
engine - clutch - countershaft - mainshaft - final driven gear - driveshafts - wheels