Car Glossary India - Index D

Dampers are also known as shock absorbers. They maintained the speed of a car when suspension's springs responds to holes and bumps in the road surface.

This is a device to clear the fog or mist that accumulates on the rear windscreen during winters or the rainy season. An array of heating elements attached in thin strips on the window’s interior evaporates the fog and gives better rear visibility.

A defroster is commonly used to heat and dry the interior surface of the front windshield. This mechanism removes moisture and fog from the inside of the windshield and warms the windshield to prevent water from freezing on the outer surface.

When a vehicle turns, it’s inside wheels cover a shorter distance than those on the outside. The differential balances this difference. It is a device that divides the torque generated by engine into two parts, allowing each part to spin different wheels at different speeds. Differential maintains the supply of torque to different wheels, thereby balancing their speed and preventing them from skidding.

Direct Shift Gearbox (DSG) is a dual-clutch gearbox designed by BorgWarner. Using this dual-clutch gearbox achieves faster gear shifts. The DSG can be operated either manually or automatically. It is better than a traditional automatic transmission, because it delivers more power and better control. Faster performance makes it better than a manual transmission as well.

DOHC (Double Overhead Camshaft) is an apparatus often used in piston engines to operate valves. They have two camshafts located within the cylinder head unlike Single overhead camshaft (SOHC) which has one camshaft. One camshaft is used to operate the inlet valves while the other is utilized to control the exhaust valves. DOHC was common in two valves per cylinder heads since decades until multivalve heads came to existence. DOHC is generally present in multi-valve heads as almost all DOHC engines have three to five valves per cylinder.

In a Drive-by Wire system, mechanical linkages between the controls of a car and the devices that actually maneuver the car are removed. Instead of operating the steering and brakes directly, the controls send commands to a central computer, which in turn instructs the car.

Drivetrain comprises the mechanical parts like clutch, transmission, driveshaft, differential, and gears including the engine that transmit power from engine to the wheels.

It is a part of automatic and Tiptronic transmissions. DSP automatically selects the optimum driving range, thereby reducing the driver’s work. The transmission automatically detects the vehicle’s driving characteristics such as speed and road conditions and adapts its shift strategy to the driving conditions.