An operator slowing a tractor-trailer needs to transition from a higher gear to a lower gear using standard double-clutching. What is the correct chronological order of the steps required to complete this downshift procedure from start to finish?
- 1Release the accelerator pedal, push in the clutch pedal, and shift the transmission lever into neutral.
- 2Release (let up) the clutch pedal while the transmission remains in neutral.
- 3Press the accelerator pedal to rev the engine to the RPM required for the lower gear.
- 4Push in the clutch pedal and move the transmission lever into the lower gear.
- 5Release the clutch pedal smoothly and press the accelerator pedal to resume driving.
Answer
The proper sequence starts with releasing the throttle, depressing the clutch, and shifting to neutral; then releasing the clutch in neutral; revving the engine to match lower-gear RPM; depressing the clutch again to engage the lower gear; and finally releasing the clutch and applying throttle.
Proper double-clutch downshifting requires two distinct clutch cycles: first disengaging the clutch to reach neutral, then releasing the clutch pedal in neutral so that revving the engine spins the transmission input shaft up to match the higher gear speed, followed by depressing the clutch a second time to slip the lever into the lower gear before final engagement.
Step-by-Step Solution
Key Concept
Basic double-clutch downshifting procedure requiring RPM matching in neutral to synchronize input shaft speed with the lower gear.
Estimated Time:1m 15s