A brake with a caliper astride a rotor. When the brake pedal is applied, the caliper squeezes the rotor between two pads lined with friction material. Disc brakes operate more efficiently at high temperatures and under wet conditions than drum brakes.
A gear assembly located between the driven wheels, that transfers the engine power coming from the transmission to the drive wheels. Differentials allow one wheel to spin at a different speed than the other when turning a corner. When a vehicle turns a corner, the outside wheels have to travel faster than the inside wheels. Differentials allow the two wheels to spin at different speeds to reduce drive-train and tire stresses.
The total volume of an engine’s cylinders, usually measured in liters or cubic inches.
DISTRIBUTOR IGNITION (DI) SYSTEM
An ignition system that uses a distributor to time and power an engine’s spark plugs. A distributor is an adjustable rotating mechanical switch driven by the engine via a gear. (See “IGNITION SYSTEM”)
DISTRIBUTORLESS IGNITION SYSTEM (aka ELECTRONIC IGNITION SYSTEM)
An ignition system which does not utilize a distributor to time and power an engine’s spark plugs. Distributorless ignition systems utilize only electrical components to perform the same functions of a distributor ignition system.This eliminates many wear items and reduces the number of parts and high-voltage wires in the ignition system. All current Hyundai models feature distributorless electronic ignition systems. (See “IGNITION SYSTEM”)
DOHC (DUAL OVERHEAD CAMS)
Refers to a pair of camshafts which are mounted above an engine’s valves in the cylinder head. One cam operates the intake valves, and one activates the exhaust valves. DOHC camshafts typically activate the valves directly, requiring fewer moving parts than other types of engine valvetrains, resulting in less inertia and wear. Also known as “twin cam”.
The shaft that transmits power from the transmission or transfer case to the differential(s). In a rear-wheel drive vehicle, the driveshaft transmits power to the differential. 4-wheel-drive vehicles may use two driveshafts, one for the front and one for the rear differential. Front-wheel-drive vehicles do not utilize a driveshaft since they combine the transmission and differential into the transaxle.
The components of a vehicle that create and transmit power to the wheels. A drive-train consists of the engine, transmission or transaxle, differential, universal joints or CV joints, transfer case (4-wheel drive vehicles), and any connecting shafts.
A braking system that utilizes a drum with two shoes and a hydraulic piston. The drum rotates with the wheel, and curved brake shoes are pressed against the inside of the drum to slow or stop the wheel. Many cars use a front disc / rear drum brake combination.
DUAL BRAKING SYSTEM
A braking system that has two separate hydraulic braking circuits to prevent a complete loss of braking in the event of a brake component system malfunction. In all Hyundai vehicles, the circuits are divided diagonally, meaning that the left front and right rear wheels are on one circuit, while the front right and rear left wheels are on another circuit. This provides better directional control should one circuit malfunction. (See “BRAKE SYSTEM” for additional.)
An exhaust system that has two separate exhaust pipes, mufflers, and other components. Dual exhaust systems are typically used in sporty or performance vehicles with V-type engines because they offer less exhaust back pressure, which increases engine power. Dual exhaust systems also have a sporty exhaust sound, and are valued for their performance look as well.
DUAL MODE DYNAMIC TOE CONTROL
Toe-in is measured by subtracting the distance between the front edges of a pair of tires from the distance between the rear edges of the same pair of tires. The toe-in dimension is positive when the fronts of the tires are turned toward the center of the car. Dynamic Toe Control helps keep the rear wheels aligned with the pavement for improved traction and precise handling.