When operating a heavy commercial vehicle equipped with an unsynchronized manual transmission, a driver must execute a standard double-clutch upshift. What is the correct chronological sequence of driver actions required to complete this procedure?
- 1Release the accelerator pedal, depress the clutch pedal, and shift the transmission lever into neutral.
- 2Release the clutch pedal completely while the transmission remains in neutral.
- 3Allow the engine RPM and transmission input shaft speed to drop to the level required for the higher gear.
- 4Depress the clutch pedal again and move the shift lever into the higher gear.
- 5Smoothly release the clutch pedal while simultaneously applying throttle.
Answer
The proper sequence begins with disengaging the current gear into neutral (clutch in), releasing the clutch pedal in neutral to let the engine and input shaft decelerate together, allowing RPM to drop to the target range, depressing the clutch again to shift into the higher gear, and finally releasing the clutch while applying throttle.
According to the official CDL manual, upshifting with a non-synchronized manual transmission requires double clutching in a five-step sequence: disengage the lower gear into neutral, release the clutch pedal in neutral so the input shaft slows down with the engine, wait for RPM to drop to match the higher gear ratio, press the clutch again to engage the higher gear, and release the clutch smoothly while applying accelerator.
Step-by-Step Solution
Key Concept
Basic double-clutching procedure for upshifting in unsynchronized manual transmissions
Estimated Time:1m 0s