Which gear is better for downhill driving?

[OJameson]

If the car has an L gear, you can use the L gear when going downhill. If there is no L gear, you can use the M gear and lock the transmission in a lower gear. For a manual transmission, you can directly shift into a low gear. Some automatic transmissions have an L gear, which stands for low, meaning low speed. When descending a steep slope, you can shift into a low gear to use engine braking for deceleration. If you rely solely on the braking system to slow down when going down a steep slope, the car's braking system may overheat and fail. When climbing some steep slopes, you can also shift into L gear to have more sufficient power for climbing.