Knowing How to Down Shift Commercial Vehicles with Manual Transmissions

Knowing how to down shift commercial vehicles with manual transmissions is important. Which of the following is the correct way to downshift?

A) Release pressure on accelerator, depress clutch, shift to neutral simultaneously, release clutch, depress accelerator, increase rpms to required level for next lowest gear, depress clutch and shift to next lower gear simultaneously, release clutch and dep
B) Hold accelerator down, depress clutch, release clutch, depress clutch while shifting to next lower gear, release clutch.
C) Release accelerator, depress clutch, shift to next lower gear, release clutch and press down on accelerator at the same time.
D) Hold accelerator pressure, depress clutch, shift to neutral and then shift to next lower gear, release clutch.
E) None of the above