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What is the tachometer used for during shifting?
- A.It shows road speed in all trucks
- B.It measures oil pressure
- C.It shows engine rpm so the driver can shift within the engine's operating range and match rpm for the next gear
- D.It replaces the need to listen to the engine entirely
Correct answer
C. It shows engine rpm so the driver can shift within the engine's operating range and match rpm for the next gear
Why
The tachometer is the shifting instrument: it tells you when the engine is high enough to upshift and what rpm to target in neutral for a downshift. Learning the rpm spread between gears turns double-clutching from guesswork into timing.
Manual topic: Shifting - Tachometer · From the General Knowledge practice bank (GK-360).