The automatic gear box
By H. Kishie Singh

THE internal combustion engine is not a particularly efficient machinery. However, it’s only one part of the automobile. Possibly the most efficient part of the automobile is the gear box — Put in 100 h.p. and 98 h.p. comes out. A transmission loss of 2 per cent only. Compare this to the engine, it works to about 25 per cent efficiency — 75 per cent of the power is lost!

Technology is being evolved to improve the performance of engines and the gear box. to refine the performance of the gear box, manufacturers have come up with the automatic gear box.

It’s nothing new. Americans have had automatic gear boxes for 60 years or more. Today over 90 per cent of cars in the USA and 70 per cent of the cars in Japan are equipped with automatic drive gears.

Automatic gear boxes are now available to Indians too. Every new breed of car now offers the driver this option. City traffic is getting more and more congested, confused and chaotic — the automatic gear box was invented for such conditions.

What is an automatic gear box? And how does it work?

The gear box, transmission or drive train as the Americans say, is used to transfer power from the engine to the wheels. The transfer of power has to be gradual because the engine is moving and the wheels are stationary. Normally this transfer of power is done through the gear box and a clutch which is worked with the left foot.

Depress the clutch, engage the gear, accelerate, release the clutch and move off. Simple. The automatic gear box is ever simpler.

The gear selector lever has markings P-R-N-D-2-1. They stand for Park, Reverse, Neutral, Drive - Two - One. The ‘moving off’ procedure is as follows. With handbrake on, put right foot on foot brake, and shift the gear selector lever into neutral.

Then start engine, move selection lever into D, release the handbrake, and accelerate so that the car moves. There is no clutch, only the brake and accelerate pedals are to be seen on the floor board. So to cope with stop-and-go traffic, the manufacturers have stop and go pedals! After putting the gear lever into ‘D’, you can drive all day long by using the two pedals.

This is really a boon for city drivers. You can bring the car to a complete halt by using the brake pedal, then move off again by just accelerating.

Should you need extra power (torque), just shift the lever into ‘2’ or ‘1’. This gives you a lower gear ratio and consequently more power. It really is an easy way to drive.

Now that the automatic gear box has arrived in India, a number of misconceptions surround the concept. They usually emanate from the side-walk mechanic who has never seen or driven a car with an automatic gear box.

The truth of the matter is that automatic gears can be said to be the most user-friendly mechanism can car offer. It’s also maintenance free, needing an oil change every 80,000 km (50,000 miles). That could be 6-8 years of driving for the average person.

They hardly ever break down, unless you shift into ‘R’ (for Reverse) at a 100 kmph! The construction is rugged and designed to last. They move the car up steep grades with ease. For down hill braking, move into 2 or 1 as the gradient demands.

The automatic gear box works all over the world, it will work in India.

The only unfavourable thing about the automatic gear box is that it costs more. A car with automatic gears will cost more than the car of the same model with conventional gears.

But then luxury and comfort do cost money!