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Synchromesh Transmission

A transmission having a synchronizer.

Synchronize

To cause two or more events to operate at the same time and/or the same speed.

Synchronizer

A device used in a manual transmission to bring a selected gear up or down to the speed of the main shaft.

Synchronous

The condition that exists when two events occur in a specified time relationship with each other, under the control of master timing signals.

Synchronous Belt

A belt having cogs or teeth that mesh in mating cogs or teeth of a pulley.

Synchronous Fuel Timing

Fuel injectors firing in direct relationship to ignition reference pulses.

Synfuel

A term used for synthetic fuel.

Syntax

The set of rules for using any language.

Synthetic Fuel

A fuel made by liquefying coal or by extracting oil from shale or tar sands.

Synthetic Lining

Brake friction material made from nonorganic, non-metallic, and nonasbestos materials. Typically fiberglass and aramid fibers.

Synthetic Oil

1. A type of engine lubricant consisting of highly polymerized chemicals. 2. A non-mineral based lubricant for use in automotive air conditioners.

Syringe

A tool with a rubber bulb and a tube or a plunger in a tube; used to suck out or force in a liquid.

System

Any set of interacting electrical or mechanical parts that are grouped together to operate as a complete entity.

System Overcharge

A term used for an overcharged system.

System Pressure

The average pressure in a system, such as the fuel-injection system.

System Protective Valves

A device that is used to protect the brake system against accidental loss of air pressure, buildup of extreme pressure, or backflow and reverse air flow in a truck braking system.

System Status (I/M Readiness Status )

A signal for emission testing which states that all the vehicle's on-board emissions diagnostics have been run. System status is not concerned whether the emission system passed or failed the test, only that the test was run.

System-dependent Recovery System

Refrigerant recovery system that relies on system components, such as the compressor, to remove the refrigerant from the system.

Systems Internationale Des Unites (SI)

The international metric system of measurement.