T
Tail lights
A set of housings that include a vehicle's brake lamps, reverse lights and rear turn signal lights.
Targa
A semi-convertible body style with a removable roof section and a full-width roll bar behind the seats.
TCS
See "Traction control."
Technical Service Bulletin
Sometimes referred to as "TSB." Please click here for the definition of this term and additional information.
Telematics
The integrated use of telecommunications in a vehicle.
Telemetrics
The integrated use of telecommunications and electronic data communications in a vehicle.
Thermostatically controlled air cleaner
A device on carbureted engines to control emissions, which contains a thermostat-controlled diverter that ducts air warmed by the exhaust manifold to the carburetor during cold conditions, and then ambient air to it once a certain temperature has been attained. This enables the engine to reach a normal operating temperature and end its fuel-rich/inefficient cold-temperature mode as quickly as possible.
Throttle & kick down lever ball studs
Lubricated pivot points for the throttle or kickdown linkages.
 
 
Throttle linkage
A collection of mechanical connections between a vehicle's accelerator pedal and its throttle body or carburetor.
Throttle system
The components used to control the volume of air to the engine.
Tie rod ends
Ball and socket parts of the steering linkage that connect the wheel spindles to the rack and pinion or center link.
Tier 1 EPA Program
The EPA's first vehicle emission program promulgated under the Clean Air Act of 1994, which set more stringent national vehicle emissions standards than had previously existed.
Tier 2 EPA Program
The EPA's second vehicle emission program promulgated under the Clean Air Act of 1994, which set more stringent national vehicle emissions standards than the Tier 1 EPA Program.
Timing belt
A "toothed" belt that drives an overhead camshaft or camshafts (and in some vehicles a water pump).
Timing belt tensioner
A spring-loaded idler wheel that automatically keeps the timing belt under enough tension to prevent the timing belt from allowing the camshaft(s) it controls to go out of sync.
Tint
A transparent plastic film applied to a vehicle's windows that reduces visible light transmission and, in some cases, rejects heat by reducing UV and infrared transmissions.
 
 
Tire diameter
The diameter, in inches, of a tire.
Tire inflator
A device used to inflate, or inflate and seal, a collapsible spare or flat tire.
Tire inflator sealant cartridge
A disposable container of pressurized sealing compound.
Tire load index
Also referred to as "load rating." A numerical value assigned to a tire by its manufacturer to indicate the tire's capability to carry a load The higher the index number, the greater its load capability.
Tire prefix
An alphabetic value assigned to a tire by its manufacturer to indicate intended uses, such as "P" for passenger cars and "LT" for light trucks.
Tire pressure monitoring system
An electronic system that measures and displays to the driver the amount of pressure in a vehicle's tires.
Tire profile
A numeric value assigned to a tire by its manufacturer to indicate the relationship between the tire's sidewall height and its tread width.
Tire size
Information displayed on the sidewall of a tire that includes its prefix and information about its dimensions, load capacity and speed rating.
 
 
Tire speed rating
An alphanumeric value assigned to a tire by its manufacturer that indicates the maximum speed the tire can safely sustain for a ten-minute period.
Title
Sometimes referred to as the "pink slip." The legal document issued by the state in which the vehicle is purchased that reflects the person or entity registered with the state as its legal owner.
Total due at signing
See "drive off fees."
Tow hooks
Metal hooks or eyelets, either fixed or removable, that are attached to a structurally sound section of a vehicle's frame and used as pickup points for tow cables.
Towing capable
A vehicle with features and equipment that make it well-suited for pulling a trailer.
Towing capacity
The maximum amount of weight a vehicle is capable of towing (according to its manufacturer).
Track
The distance from the center plane of one wheel to the center plane of its opposing wheel.
Traction control
Also known as "traction control system," or "TCS." A safety feature that regulates wheel spin and prevents loss of control under acceleration by ensuring maximum traction and contact between the tires and the road (by adjusting brake pressure to one or more wheels, closing the throttle, or reducing the fuel supply to at least one or more cylinders).
Traction control system
See "Traction control."
Trade-in
A vehicle that is currently owned by the purchaser of a new or used vehicle from a dealer and that is exchanged for the newly purchased vehicle in order to reduce its net price.
 
 
Trailer hitch
A metal device attached to a structurally sound section of a vehicle's frame that is used to support a trailer while coupling it to the vehicle.
Trailer hitch mountings
Trailer hitch attachment points on the body or chassis.
Trailer wiring
A flat, four-way, weatherproof connector located near a vehicle's trailer hitch used to complete the circuits for a trailer's ground, running, left signal, right signal and break lights.
Transaxle
A combination transmission and differential/drive axle assembly.
Transfer case fluid
Lubricant used in the transfer case.
Transmission modes
Driver-selectable transmission settings that change drive ratios and/or shift points for fuel economy or performance.
Transmission overdrive
A final gear ratio for an automatic transmission that has an output speed greater than its input speed, which increases highway fuel economy.
 
 
Transmission type
The type of transmission: automatic, manual, shiftable automatic or automated manual.
Trip computer
An electronic device used to calculate and display trip information, such as distance traveled, average speed and fuel economy.
T-top
A vehicle roof with removable panels on either side of a rigid bar, running from the center of the vehicle's A pillar to the center of its B pillar.
Turbocharger
Sometimes referred to as a "turbosupercharger." A device that uses an exhaust-driven turbine to force air into an internal-combustion engine in order to increase engine power.
Turn signals
Flashing amber-colored lights that indicate when a vehicle's driver intends to make a turn or lane change.
Turning circle
Also referred to as "turning diameter." The diameter of the circle made by a vehicle in a full-lock 360 degree turn.
12V DC outlet
An electrical socket receiving 12v DC current produced and stored by a vehicle's charging system.