Auto Terms G

Galvanized Steel

A specially zinc-coated steel used on many major painted panels and in key unpainted areas of a vehicle to help prevent rust and corrosion.

Gap Insurance

Insurance that will cover the difference between the replacement cost paid by conventional insurance and what is owed on the lease in the case the car is totaled or stolen.

Gas Filled Shock Absorbers

A nitrogen gas chamber is used to pressurize the shock absorber in place of the traditional air/oil combination. Gas filled shock absorbers provide more stable damping in a variety of conditions and thus improves ride and road contact.

Gear Ratio

The number of revolutions a driving (pinion) gear requires to turn a driven (ring) gear through one complete revolution. For a pair of gears, the ratio is found by dividing the number of teeth on the driven gear by the number of teeth on the driving pinion gear.

Generator

A device that converts mechanical energy into electrical energy. It can produce either AC or DC electricity. Seldom used in automotive applications, it has been replaced by the alternator.

Gray Market Vehicle

Cars that have been imported into the country but not through authorized retailers. They may not meet American safety and emission standards. These cars may have significantly lower values than cars imported through normal channels.

Halogen Headlamp

A sealed-beam headlamp with a small inner bulb filled with halogen which surrounds a tungsten filament. Halogen headlamps may increase luminous intensity at the road surface by 50 to 80 percent, as compared to the long-conventional sealed-beam headlamp systems. Many halogen headlamp systems incorporate high-beam and low-beam in one element, enhancing their serviceability.

Heads Up Display

The digital projection of pertinent instrument data onto the lower portion of the windshield on the driver's side. The driver does not have to take his eyes off the road to read his instrument panel.

Independent Suspension

A term used to refer to any type of suspension system that allows each of the two wheels of a given axle to move up and down independently of each other.

 

Lease

A contract granting the use of a car for a specified period of time in return for a set fee. Leases may be classified as open ended or closed ended.

Limited Slip Differential

A differential in a rear-drive vehicle fitted with a mechanism that limits the speed and torque differences between its two outputs. Limited slip ensures that some torque is always distributed to both wheels, even when one is on a very slipper surface.

Lock Up Torque Converter

A torque converter that contains a special clutch that forms a solid connection between the engine output shaft and the transmission input shaft when a certain, pre-set speed is attained. This reduces transmission friction losses and increases efficiency.

MacPherson Strut

A suspension system that consists of a combination coil spring and shock absorber in one compact unit at each wheel. With this "independent" suspension design, road shocks at one wheel are not transferred to the opposite wheel. MacPherson struts use fewer parts, meaning a reduction on weight and fewer elements that could wear out.

MSRP

Manufacturer's Suggested Price. MSRPs do not include applicable destination charges, state and local taxes, license fees, optional equipment or special items or services.

Multi-Port Fuel Injection (MFI)

Multi-Port Fuel Injection uses individual fuel injectors to spray fuel into each intake port, bypassing the intake manifold.

Octane Rating

A unit of measurement on a scale intended to indicate the tendency of a fuel to detonate or knock based on the percentage of isooctane in the fuel. The higher the rating, the higher the percentage of isooctane and therefore the greater the resistance to detonation offered by the fuel.

Open End Lease

A lease in which the lessor is not responsible for the value of a vehicle when the lease is done. Under this arrangement the lessee is responsible for the difference between the current actual market value at the end of the lease and the residual value. Also known as a "finance" lease.

Overdrive

A transmission in which the highest gear ratio is less than a one-to-one ratio. This means the drive shaft turns faster than the engine crankshaft. The overdrive feature saves fuel and, because the engine runs slower, engine wear and noise are reduced.

Overhead Cam

The type of valve train arrangement in which the engine's camshaft is mounted above the cylinder head(s). When the camshaft is placed close to the valves, the valve train components can be stiffer and lighter, allowing the valves to open and close more rapidly and the engine to run at a higher RPM. In a single overhead cam (SOHC) layout, one camshaft actuates all of the valves in a cylinder head. In a dual overhead camshaft (DOHC) layout, one camshaft actuates the intake valves, and one camshaft operates the exhaust valves.

Overhead Valve Engine (OHV)

An engine with both intake and exhaust valves placed directly over the piston. In this design, the camshaft is located in the block, and the valves are actuated by pushrods and rocker arms.

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