Most people are familiar with Automatic car gear selector positions Park, Reverse, Neutral and Drive. Not every one knows drivers can manually select gears (or speeds) in an auto car.
All auto cars have some way to at least select lower gears or speeds where extra control is needed. Even Hybrid cars have some type of Brake mode for going down steep hills safely.
In this example we are choosing a lower speed to keep the car at a safe speed when negotiating a steep decent. At the top of the steep hill, we are shifting into low gear then shift to a slightly higher gear as we want to go faster. (South Australian Driving Companion Logbook Task 6 for Learner Drivers).
In truth, we could easily have controlled the car down this hill just using the brakes but what if it were a much longer decent. What if we were travelling down hill for 30 to 40 minutes down a steep mountain road or maybe towing a heavy trailer of caravan down a long steep hill like the decent into Adelaide on the South Easter Freeway.
Choosing a lower gear and using the engine to help us stay slower meaning we don't over using the brakes. If we simply use the brakes to stay slower down a steep hill, they are likely to over-heat and stop working. By then it may be too late to use gears to slow down. You simply get faster and faster down that mountain road unable to slow for bends or anything else that gets in you way.
Truck drivers know they "Must Use Low Gear" on steep descents. Car drivers need to know it too. You won't need to use this technique often but the day you will really need to know what to do.
When choosing a lower gear or slower speed in your automatic car, take care not to over-rev the engine and remember, it is still OK to use brakes to keep the car at a safe speed. Selecting the slower gear simply means you can save you brake particularly be coming completely off the brake pedal for periods of time, releasing the brakes an allowing them to cool down before applying again to stay at a safe speed.
