Dictionary of Automotive Terms Abbreviations

DICTIONARY OF AUTOMOTIVE TERMS - "Tr"

TR:: Acronym for thermal reactor

TRA:: Tire and Rim Association.

Track:

Front track is the distance between the center of the left front wheel and the center of the right front wheel when the vehicle is set to its normal ride height and wheel alignment specifications. Rear track is the distance between the center of the left rear wheel and the center of the right rear wheel. They are not always the same.
A designated course or roadway where vehicles race.

Also See:
axle track
eight-track
one-groove track
oval track
short track
tri-oval track
warning tracks

Track arc:: The path travelled by a road wheel during a turn

Track bar:: See panhard rod

Track control arm:: See transverse link

Tracked:: See crab-tracked

Tracking:

The alignment of the vehicle with respect to axle centers of a vehicle being in the same plane, rear tires following front tires and trailer following the tractor, in the attitude designed. Correct tracking is when the rear wheels of a vehicle follow the same line as the front wheels. Also see straight-line tracking.
A line of carbon along which electricity leaks. See carbon tracking.
shunt firing of a spark plug.

Tracking mark:: A telltale sign on the distributor cover or ignition cables indicating a leakage of current

Track rod:: One of the transverse bars connecting the steering system to the steering arms; the link between the pitman arm and the steering-knuckle arm.
Also See:
panhard rod
tie rod

Tract:: See intake tract

Traction:

Pulling force.
The force of adhesive friction exerted by a body on the surface on which it moves.
Tires ability to grip the road. Higher traction allows greater braking and cornering force to be generated.

Also See:
electronic traction control
liquid traction
low-speed traction control

Traction avant:: A French term for front-wheel drive

Traction bar:: An articulated bar or link attached to both frame rear axle housing to prevent spring windup (with resultant wheel hop) during heavy acceleration or braking. Also see panhard rod.

Traction control:

A system that helps prevent front-wheel spin on slippery or gravel surfaces during acceleration at speeds up to 40 kph (25 mph).
A means of preventing wheelspin due to acceleration, either by braking the spinning wheel or reducing engine power.

Also See:
electronic traction control
low-speed traction control

Traction control system:: See:
anti-spin regulation
anti-spin regulation traction control system

Traction differential:: See limited-slip differential.

Traction engine:: A steam or diesel engine used for hauling heavy vehicles on roads or over difficult terrain.

Traction limited grade:: Steepest negotiable grade where traction is the limiting factor.

Tractive conversion:: See stall torque ratio

Tractor:: Truck portion of combination or train. Also called "semi," "semi-tractor," "truck tractor," or "tractor-trailer."
Also See:
semi-tractor
truck tractor

Tractor-trailer:: See tractor.

Trade:: See:
agreement on Tariffs and Trade
american Free Trade
free Trade Agreement of the Americas
general Agreement on Tariffs and Trade
North American Free Trade Agreement

Trade agreement:: See:
American Free Trade Agreement
Canada-U.S. Free Trade Agreement
free Trade Agreement of the Americas
North American Free Trade Agreement

Trade Agreement of the Americas:: See Free Trade Agreement of the Americas

Trade-in price:: The price of your old car when you are selling it in part exchange for another one

Trade Organization:: See world Trade Organization

Traffic:: A road with moving vehicles.
Also See:
heavy traffic
light traffic
rush-hour traffic

Trafficator:: See semaphore indicator

Traffic circle:: An intersection of several roads where the traffic goes around a central circle and goes out another road. Although it is a rapid way of negotiating an intersection, many people are intimidated by it because of its unfamiliarity. The British term is "roundabout"

Traffic island:: A raised area in the middle of a road designed to separate two flows of traffic and to provide a safe temporary stopping place for pedestrians crossing the road

Traffic jam:: A number of vehicles stopped behind one another on a road

Traffic light:: A series of red, amber, and green lights placed at the intersection to regulate the flow of traffic

Trail:

A path used by pedestrians and smaller vehicles (e.g., bicycles, quads, snowmobiles, etc.).
The path that a wheel makes.

Also See:
caster trail
pneumatic trail

Trail bike:: A dual purpose motorcycle for use on or off-road

Trail braking:: A driving technique in which the driver begins to brake before entering a turn and then continues to brake as he eases into the corner. As cornering forces build, the driver gradually feathers off the brakes -- trading braking power for cornering grip. By increasing the vertical loading -- and thus the traction -- at the front tires, trail-braking can improve a car's turn-in.

Trail distance:: The distance from the point at which the cornering force acts to the center of the wheel or steering axis.

Trailer:

Platform or container on wheels pulled by a truck or tractor.
Distance between fifth wheel pin and center of rear axle (or center between tandems).
A unit which contains camping equipment and is pulled behind a vehicle.

Also See:
boat trailer
camping trailer
fifth-wheel travel trailer
flatbed trailer
folding camping trailer
full trailer
hard-sided trailer
hard-top trailer
maximum trailer weight
semi-trailer
soft-sided trailer
soft-top trailer
tractor-trailer
travel trailer

Trailer tire:: A small tire often 12" with a load range "B" and a capacity rating of 850 lbs

Trailer towing package:: See trailer-towing package.

Trailer-towing package:: An optional equipment which usually includes a heavy-duty suspension a larger radiator a transmission cooler and a rear bumper with a trailer hitch. This improves handling and allows a vehicle to haul a heavy trailer.

Trailer weight:: See maximum trailer weight

Trailing:: See parallel trailing link suspension

Trailing arm:: Type of independent rear suspension in which the pivot axis is exactly across the vehicle, or perpendicular to the longitudinal axis. This means the wheels are always upright relative to the body and hence leaning with the body in a corner. Widely used at the rear of front-wheel-drive cars. Also see semi-trailing arm.

Trailing axle:: See a dead axle

Trailing brake shoe:: The brake shoe that is installed facing the rear of the vehicle. Also called secondary brake shoe or reverse brake shoe.

Trailing edge:: The rear edge (e.g., of a body panel). Compare leading edge

Trailing link:: A front suspension linkage that is aligned to resist longitudinal motions in a wheel; it is mounted to the chassis ahead of the wheel. The links pivot forward of the axle. Also see parallel trailing link suspension

Trailing link suspension:: See parallel trailing link suspension

Trailing shoe:

A shoe whose friction surface trails behind the shoe pivot and is pushed away from the drum by drum rotation.
A British term for a secondary shoe -- a shoe of a brake drum system whose activated end faces away from the approaching drum

Trailing throttle:: An oversteer handling situation of rear drive cars. When the throttle is closed the engine applies compression braking so that the rear suspension alignment changes. This change causes the rear tires to lose traction which promotes a lateral slide.

Train:: See:
drivetrain
gear train
gross train weight
member of the gear train
powertrain
road train
strain in the drive train
valvetrain
wind trainer.

Trainer:: See wind trainer.

Train station:: Trucker slang for Traffic court that fines everyone as in "Get out your money traffic court is a real train station today."

Train weight:: See gross train weight

Tram:

A British term for a streetcar.
A small train used to haul ore at a smelter.

Tramcar:: A British term for a streetcar

Tram gauge:: An alignment tool -- a long bar that has two or three parallel pointers extending at right angles and attached so that they can be moved to any position along its length

Tramline:: The rails along which a tram runs

Tramlining:: The tendency of a vehicle's tires (often when of low profile) to follow a ridge or rut in the road's surface

Tramp:

A hopping or oscillating motion of the front wheels usually caused by incorrect balance or when a high inflation tire has been run empty.
The action of rapidly depressing the throttle pedal.

Also See:
axle wind up
axle tramp
wheel tramp

Tramway:: The rails along which a tram runs

Tranny:: Colloquial name for "transmission."

Trans:: Abbreviation for "transmission."

Transaxle:: A drive setup in which the transmission gearbox
clutch final drive, and differential are combined into a single unit connected directly to the driveshaft. It is used mostly in rear-engine cars like the Corvair, but is also found in some front-wheel drive cars and some performance cars where a front engine/rear transaxle gives better overall balance (such as the Alfa Romeo Alfetta). Also see rear-wheel drive transaxle

Transceiver:: A radio device which can transmit a signal and opposite to a receiver

Transducer:: A device for transferring power which is generated in one system to another system in the same or a different form, e.g., electrical to mechanical.; Any device that converts an input signal into an output signal. Used to actuate electric or vacuum servo motors in an automatic temperature control system.; Device turned on by change of power from one source for purpose of supplying power in another form to second system. Also see negative transducer EGR valve

Transducer EGR:: See negative transducer EGR valve

Transducer EGR valve:: See negative transducer EGR valve

Transfer:: See:
decal
heat transfer
load transfer
weight transfer

Transfer box:: See transfer case

Transfer case:: An auxiliary device in a 4-wheel-drive vehicle that allows power to be delivered to both axles. Normally the transfer case incorporates a shifting device so that the front drive can be disconnected, if desired, for running on pavement. Also see four-wheel drive.

Transference:: See load transference

Transfer molding:: The development of compression molding where powder polymer is placed in a small chamber adjacent to a tool mold and when heated, is forced into the tool cavity. Also see molding

Transfer moulding:: British term for transfer molding

Transfer passage:: The passage connecting the crankcase of a two-stroke engine with the combustion chamber

Transfer plate:: An adapter plate in the control valve assembly of an automatic transmission, used to direct the fluid flow between adjacent valve bodies

Transfer port:: A channel in the block of a two-stroke engine where the air-fuel mixture enters the combustion chamber and exits out another transfer port after it burns.

Transfer port cover:: The transfer passages of most two-stroke engines are accessible from the outside to allow for maintenance, they are covered by the transfer port covers for regular engine operation

Transfer ports:: The holes that deliver fuel from the idle circuit during the transition from curb-idle to the main metering circuit. Located just above the throttle plates. At curb idle, off-idle ports function as an extra air bleed for further emulsification of the idle mixture; but as vacuum moves up the carburetor bore when the throttle plates are opened, they become fuel discharge ports. Either one or more holes, or a single slot (slots are usually used because they are cheaper to manufacture). Also called off-idle discharge ports

Transfer pump:: An in-tank pump, used on many Bosch and some other fuel injection system, that boosts the fuel pressure slightly before the fuel is sucked into the main pump, in order to prevent cavitation. Also, part of the fuel injection pump for a diesel engine, boosts fuel pressure from around 20 psi to about 130 psi, depending on the pump and the engine speed

Transformer:: An electrical device with an arrangement of copper coils with an iron center, used to increase or decrease electrical voltage. A vehicle ignition coil transforms the voltage from 12 volts to upward of 20,000 volts.; Electromagnetic device which transfers electrical energy from primary circuit into variations of voltage in secondary circuit.
Also See:
air transformer
ignition transformer
voltage transformer

Transformer-rectifier:: Combi nation transformer and rectifier in which input ac current may be varied and then rectified into dc current.

Transistor:: Electronic device commonly used for amplification. Similar in use to electron tube. Depends on conducting properties of semiconductors in which electrons moving in one direction are considered as leaving holes that serve as carriers of positive electricity in opposite direction.; See ignition transistor

Transistor ignition:: A form of ignition system which uses transistors and a special coil. The conventional distributor and point setup is used, but the points merely serve to trigger a transistor which switches the heavy primary current. With the transistor unit, the voltage remains constant, thus permitting high engine rpm without resultant engine "miss." Transistors are much more efficient switches at high engine speeds and in addition they don't burn, pit or change gap spacing. The advantages of these systems include greatly increased point life, generally better starting because of improved contact condition and voltage output not greatly affected by breaker point dwell time which results in better high-rpm performance. Also point life is greatly extended as the transistor system passes a very small amount of current through the points.

Transistorized coil ignition:: (TCI) See transistor ignition

Transistorized coil ignition with Hall sensor:: (TCI-H) See transistorized ignition with hall generator

Transistorized ignition:: (TI) An ignition system using a transistor as a power switch; available as breaker-triggered TI with contact breaker or as breakerless TI with magnetic pick-up or hall generator. Also see breaker-triggered transistorized ignition

Transistorized ignition with inductive pulse generator:: See transistorized ignition with inductive pick-up

Transistorized ignition with Hall generator:: (TI-H) There are two types of TI-H: in one version, the dwell angle is determined by the width of the rotor vanes in the distributor; the other version contains a circuit for automatic dwell angle control incorporated in the electronic control unit

Transistorized ignition with inductive pick-up:: (TI-I) A transistorized ignition system with a magnetic pick-up in the distributor and an electronic control unit for signal processing, with current and dwell angle control

Transistorized ignition with magnetic pick-up:: (TI-I) A transistorized ignition system with a magnetic pick-up in the distributor and an electronic control unit for signal processing, with current and dwell angle control

Transit:: See mass transit system

Transit system:: See mass transit system

Transmission:

A device (full of gears) that uses gearing or torque conversion to effect a change in the ratio between engine rpm and driving wheel rpm. When engine rpm goes up in relation to wheel rpm, more torque but less speed is produced. A reduction in engine rpm in relation to wheel rpm produces a higher road speed but delivers less torque to the driving wheels.
Heat loss or gain from a building through exterior components such as windows, walls, floors, etc.

Also See:
automatic transmission
auxiliary transmission
belt transmission
bevel gear transmission
C-matic transmission
continuously variable transmission
dual-range transmission
electronic transmission control
electronic transmission
five-speed transmission
four-speed transmission
high/low range transmission
hydrostatic transmission
infinitely variable transmission
J gate transmission shifter
manual transmission
overdrive transmission
planetary transmission
powershift transmission
progressive transmission
selective transmission
semi-automatic transmission
six-speed transmission
standard transmission
stepless transmission
synchromesh transmission
three-speed transmission
two-speed transmission
variable belt transmission
variable transmission
variomatic transmission
viscous transmission

Transmission adapter:: A unit that allows a different make or year transmission to be bolted up to the original engine.

Transmission, automatic:: See automatic transmission.

Transmission control:: See electronic transmission control

Transmission controlled spark:: (TCS) A system to reduce the emission of nitrous oxides by which a vacuum solenoid and a switch in the transmission system prevents the distributor's vacuum advance mechanism from operating in the lower gears and at low speed

Transmission control module:: (TCM) An electronic automatic transmission control unit which computes data on the actual operating conditions of the vehicle and generates corresponding signal pulses for the solenoid valves of the hydraulic control system; may also exchange data with other electronic control units

Transmission control system:: A hydraulic or electro-hydraulic system which controls the changes of ratio in automatic transmissions corresponding to engine load, vehicle speed, positions of the selector lever, and shift mode button

Transmission, conventional:: See standard transmission.

Transmission cover:: A removable part of the floorpan usually located at the front end of the center tunnel in cars with a longitudinally mounted engine; provides better access to the top of the transmission for maintenance and adjustment purposes

Transmission extension housing:: A rear-wheel drive transmission housing enclosing an extended main shaft, sometimes accommodating the gear lever and associated mechanism

Transmission fluid:: (ATF) A superthin oil that fills the automatic transmission system so that it can run on hydraulic pressure. It can also be used in some power-steering pumps. It is sometimes used to clean the inside of a carburetor.

Transmission governor:: A governor on the output shaft of a hydraulically controlled transmission converts line pressure into governor pressure. In electro-hydraulically controlled transmissions, the governor is replaced by a sensor.

Transmission housing:: The outer shell which contains the transmission gears.

Transmission input shaft:: A shaft which transmits power from the clutch to the gearbox

Transmission output shaft:: A shaft which transmits the power out of the transmission

Transmission powertrain control module:: An electronic module or a computer that receives input from various transmission related sensors to determine the operating condition of the transmission at a particular moment. The transmission module or computer responds to these signals and/or input from the PCME by sending signals to various transmission controls to meet predetermined operating instructions.

Transmission shifter:: See J gate transmission shifter

Transmission, standard:: See standard transmission.

Transmission tunnel:: A semicircular or oval bulge along the longitudinal axis of the floorpan to accommodate the propeller shaft and, at its front end, the transmission, enabling the shaft and transmission mounting position to be raised to the floorpan level, thus providing better protection for the drive train against road dirt and obstacles

Transmitter:: A radio remote control system device that transmits electrical or radio signals. Also see emergency transmitter

Transom:: See stern transom

Transom beam:: The aftermost transverse deck beam

Transom frame:: The aftermost transverse side frame

Transplants:: An overseas production plant; in most cases, the term refers to automotive vehicles produced in the USA, Canada, or Europe at Japanese-owned factories (e.g., a Toyota plant in Cambridge, Ontario, Canada)

Transporter:: A large articulated truck for transporting several cars (on two or three decks)

Transom stern:: A square-ended stern used to provide additional hull volume and deck space aft and to decrease resistance in some high speed ships.

Transverse arm:: A suspension arm not split into two separate sections as is an A-arm. Often used as the bottom locating link with MacPherson strut suspension. Also called "lateral arm." Also see MacPherson strut.

Transverse cable:: See stirrup cable.

Transverse engine:: An engine that is mounted laterally (i.e., left to right) between the drive wheels (rather than longitudinally -- front to back), often found on cars with front-wheel drive. Also called "east-west layout"

Transverse flow scavenging:: See cross scavenging

Transverse leaf spring:: A leaf spring that is mounted so that it is at right angles to the length of the vehicle.

Transverse link:: Any suspension link that provides lateral support for wheels; on front suspensions, a typical design is the Y-shaped wishbone

Transverse mount:: The engine is mounted sideways. The fan belt will be over one of the tires rather than in the very front of the vehicle. This is common in front-wheel-drive cars. This enables the car to be more compact because the space under the hood is used more efficiently and provides better weight distribution. See transverse engine.

Transverse rod:: See panhard rod

Transverse torsion bar:: See:
torsion bar

Trap:

The area over which the vehicle is raced for timing purposes.
A pedal on a bicycle into which the foot is locked in place.
Also See:
rattrap
A filter or separator

Also See:
activated charcoal trap
flame trap
oil trap
pm trap

Trap oxidizer:: In diesel particulate filters, a means of burning the particulate charge trapped in the filter element, to prevent the filter from clogging and to restore filtration capacity; usually a catalyst coating that promotes oxidation of carbon particulates to harmless carbon dioxide

Trapped volume:: A clearance volume

Trapping efficiency:: In a two-stroke engine, the mass of fresh charge in a cylinder actually retained, divided by the mass of fresh charge supplied per cycle

Traps:: See trap.

Trauma fee:: $6 per $1000 of car value levied annually in Washington State (and others) to support trauma units in hospitals that care predominantly for car crash victims.

Travel:

The distance an object can move.
The distance that suspension components, forks and shocks, move up and down when the bike rides over bumps.
Measurement of the total distance that a shock can move.

Also See:
clutch pedal free travel
direction of travel
fifth-wheel travel trailer
free travel
pedal free travel
pedal travel

Travel trailer:

A recreational unit which is pulled behind a vehicle and has similar amenities that are featured on a Class A RV. Some have slideout sections to extend the living space. They can sleep up to eight people. They feature a small bedroom, bathroom (toilet, shower), fully equipped galley (cooking facilities, refrigerator, sink, faucets), water tanks (fresh water, grey water, black water), heater, air conditioner, a LP (propane) gas supply, and a separate 100-125 volt electrical system Most tow vehicles must be equipped with a load distributing hitch and other special devices designed to control the sway of the trailer.

Average weight: under 4000 pounds
Average length: 10 ft to 35 ft
Average price: $10,000 to $100,000

Also See:
fifth-wheel travel trailer

Tray:: See:
battery tray draining tray

Tray table:: A table that folds out of the back of the front seat (similar to those found on airplanes)

TR-Denioc rim:: See TD rim

TR-Denioc wheel:: See TD wheel

Tread:

The distance between the two front or two rear wheels.
Portion of the tire which contacts the roadway.
The pattern of the outside circumference surface of a tire.

Also See:
asymmetrical tread
cracking tread
directional tire
directional tread
new tread
non-directional tread
nu-tread
precured tread rubber
self-cleaning tread
symmetrical
tire tread
wide treads.

Tread bar:: Raised portions of rubber that make up me tread of the tire, separated by grooves that are arranged laterally, providing traction in the forward or rearward direction.

Tread block:: Raised portions of rubber that make up part of the tread pattern They are often present in the shoulder area and are more or less rectangular in shape.

Tread depth:: The measurement from the bottom cm of the tread groove to the top of the tread expressed in millimeters or 32nds of an inch. The legal minimum amount of tread is 1.6 mm (2/32") across three-quarters of the tire width

Tread depth gauge:: A simple compact device for measuring the depth of tread, consisting of a spring-loaded plunger calibrated in millimeters or 1/32 of an inch

Tread gauge:: See tire tread gauge

Tread groove:: One of several channels cut in the tread that disperses road water or provides traction in mud and snow

Tread pattern:: Tread patterns differ according to the manufacturer of the tire but they all have in common the aim of dispersing water from the road, to enhance grip, to avoid aquaplaning, to disperse heat, and to reduce noise and wear

Tread pattern percentage:: (TPP) The percentage of grooves and sipes to the overall surface of the tread

Tread profile:: The shape of the tread as seen in cross section

Tread rib:: The continuous raised portions of rubber that run circumferentially (straight or in a zigzag pattern) making up the tread on the tire. Also called the tread bar

Tread roller:: A roller, either manual or power, used to help apply me tread rubber, remove trapped air and obtain adhesion. Also see stitching.

Tread rubber:: See precured tread rubber

Tread separation:: Pulling away of the tread from the tire casing.

Tread squirm:: The flexibility in the tire tread between the surface of the tread and the tire carcass. Snow tires, with their small, deep, unsupported tread blocks, have a large amount of tread squirm. Slick racing tires, which have no tread pattern, have very little squirm.

Tread wear indicator:: See tread-wear indicators.

Tread-wear indicator:: See tread-wear indicators.

Tread wear indicators:: See tread-wear indicators.

Tread-wear indicators:: Bars of hard rubber that appear across the treads of a tire. They are 1.5 mm (1/16") above the base of the tread (the legal limit. They become visible when the tread has been worn down so that only 1.5 mm (a sixteenth of an inch) of tread is left. The legal limit may be shown on the sidewall by a symbol or by the letters TWI

Treatment:: See:
anodic treatment
anti-rust treatment
chromate treatment
exhaust treatment
full dip treatment
heat treatment
mechanical surface treatment
most-favoured-nation Treatment
no rinse treatment
phosphate treatment
pvc underbody treatment
tin immersion treatment
zinc immersion treatment

Tree:: See:
christmas tree
triple tree
wheel tree

Triac:: Three-lead semiconductor that allows current flow in two directions when a preset voltage is applied at one of the leads.

Trial:: See field trial

Trials:: A type of ATB bicycle or off-road motorcycle competition that tests riders not on speed but on ability to maintain balance while navigating around and over numerous obstacles such as rocks, trees, and steep, slippery terrain. Points are deducted if the rider puts his feet on the ground, goes outside the marked course, or fails to clear an obstacle. Also see sea trials

Triangle:: See:
front triangle
main triangle
rear triangle
warning triangle

Triangle split system:: See dual brakes -- especially the picture.

Triangle-split system:: See dual brakes -- especially the picture.

Triangular ground electrode:: A ground electrode with three bridges attached to its end points, which form a link to the threaded shell

Triangular safety reflector:: See warning triangle

Triangulation:: The arrangement of the stabilizing tread plies whereby their cords form tiny triangles in the Michelin 'X. radial truck tire.

Triathlon tire:: Triathlon tires are usually 650c. Although they are sometimes referred to as 26 inch, they are not compatible with tires meant to fit ATB rims.

Triathlon wheel:: A wheel consists of a hub, rim, and spokes. Triathletes often prefer to use smaller size wheels than road riders. Triathlon specific wheels are size 650C.

Tri bars:: See aerobars

Tricar:: An old name for a three-wheeler

Tricarbonyl:: See methylcyclopentadienyl Manganese Tricarbonyl

Trichlorethene:: (C₂HCl₃) A cleaning solvent

Trichlorethylene:: (C₂HCl₃) A cleaning solvent

Trichlorotrifluoroethane:: Complete name of refrigerant R-1 13. Group 1 refrigerant in rather common use. Chemical compounds which make up this refrigerant are chlorine, fluorine, and ethane.

Trick:

A description of a whole motorcycle which is "really cool," "really hot," "really new" and unobtainable or expensive.
A component of a motorcycle which is unique

Trickle charge:: A continuous charging of a storage battery at a low rate to keep it in a fully charged condition for a period when no current is drawn from it

Trickle charger:: A small battery charger which delivers less than five amperes

Tricycle:: A three wheeled vehicle (usually pedal-powered) where there is a single front wheel and two rear wheels. A three-wheeled, early-type open automobile using bicycle wheels and a steel-tube frame. Also see trike.

Tri-drive:: A vehicle having three rear driving axles.

Triflex:: A stretchable laminate of Polartec Fleece and Nylon/Lycra. Windproof, waterproof and breathable. Triflex creates the warmest cold weather cycling gear.

Trigger box:: See ignition control unit

Triggering device:: An electronic control unit that activates the air bag in a crash. It contains a deceleration sensor, a Hamlin switch and a check circuit

Triggering unit:: An electronic control unit that activates the air bag in a crash. It contains a deceleration sensor, a Hamlin switch and a check circuit

Trigger wheel:

A rotor of a magnetic pick-up integrated into the distributor, with as many teeth as the engine has cylinders.
A Hall generator rotor with an outer ring interrupted by one or several Hall windows, depending on its purpose

Trike:: A tricycle. A motorcycle that has been converted to a three-wheeled unit. Sometimes the rear two wheels are powered by a small automobile engine.

Trim:

Nonfunctional metal or plastic molding, frames and other decorative additions to vehicle bodies and interiors. Also called hard trim.
A vehicle's interior decoration, including the upholstery, roof and door linings. Also called soft trim.
The difference between the draft forward and the draft aft. A ship is trimmed by adjusting the location of fuel, cargo, ballast, etc.

Also See:
door trim
edge trim
hard trim
head trim
interior trim
soft trim
wheel trim

Trimaran:: A triple hulled vessel

Trim emblem:: See wheel trim emblem

Trim level:: A vehicle designation assigned by vehicle manufacturers that represent specific equipment packages.

Trim panel:: The decorative interior panel

Trim panel release tool:: A fork-like tool used to pry out fasteners on interior panels without breaking them or damaging the car

Trim rim:: See wheel trim rim

Tri-oval track:: An oval track with an extra rounded corner. Daytona is a tri-oval track.

Trip computer:: A computer with a multifunction display; supplies the driver with trip information such as range, ETA, distance to destination, time, fuel economy, fuel consumption, average speed, accumulated trip miles, elapsed time since last reset

Tri pin:: A device which is attached to a steering wheel to allow disabled people to insert a hand into its bracket in order to steer a vehicle.

Triple:: See touring triple

Triple clamp:: The devices which secure the handlebar to the triple tree on a motorcycle. Named because is has three clamping points -- one for each of the two front forks, and one for the steering tube.

Triple point:: Pressure-temperature condition in which a substance is in equilibrium (balance) in solid, liquid, and vapor states.

Triple tree:: The yoke that supports the handlebar on a motorcycle.

Triplex chain:: A chain with three rows of rollers.
Also See:
duplex chain
simplex chain

Trip meter:: An instrument which measures the distance a vehicle travels from the last time it was reset and runs in conjunction with the odometer

Trip mileage counter:: An instrument which measures the distance a vehicle travels from the last time it was reset and runs in conjunction with the odometer

Tripod jack:: A device for lifting a vehicle.

Tripod joint:: A constant velocity joint with three balls engaged in curved grooves

Trip odometer:: An auxiliary odometer that may be reset to zero at the option of the driver. It is used for keeping track of the mileage on trips up to one thousand miles.

Tripping bracket:: Flat bars or plates fitted at various points on deck girders, stiffeners, or beams as reinforcements to prevent their free flanges from tripping

Trip recorder:: Incorporated in the speedometer, the trip recorder indicates the mileage (in miles or km) covered during a particular journey (trip), either mechanically or electronically; trip figures can be reset to zero by turning or pushing a reset button. Also called a trip meter trip mileage counter or trip odometer

Triumph:: A vehicle brand of which the Dolomite 8 and Gloria 6 models only from 1925-1948 are classic cars. The 1953-63 TR2/TR3 models are milestone cars.
Click image for books on Triumph

Trk:: See 8 trk

TR number:: Code number of the tube valves and flaps set by Tire and Rim Association.

Trolleybus:: An electrically powered public transport bus that takes its power from overhead wires

Trolley jack:: A hydraulic jack with swivel wheels

Troposphere:: Part of the atmosphere immediately above the earth's surface in which most weather disturbances occur.

Trouble code:

Engine self diagnosis. Electronic control module questions sensor reading and stores code for which circuit trouble is located
Numerical codes created y an electronic module with self-diagnostic capabilities and normally stored in the module memory. They result from a system self-tes that indicates a circuit or subsystem problem, or a general condition that is not within limits. Often called fault or service codes, they are now referred to as diagnostic trouble codes.

Troubleshooting:: Diagnosing engine, transmission etc., problems by various tests and observations.

Trouble-shooting light:: A light with a long lead, used in garages to inspect the underside of cars and under the hood

Trough:: See wiring trough

Troy weight:: A system of measurement of weight used for gold, silver, and platinum

Troy ounce:: A measurement of weight where one troy ounce equals 31.10 grammes. In writing, it is often shortened to troy oz. after figures, e.g., 25.2 troy oz. Troy weight is divided into grains, pennyweights (24 grains = 1 pennyweight), ounces (20 pennyweights = 1 ounce) and pounds (12 troy ounces = 1 pound). Troy weights are slightly less than their avoirdupois equivalents; the troy pound equals 0.37 kg or 0.82 lb avoirdupois

TR rim:: A safety rim developed by Michelin with a flattened rim flange and run-flat potential

Truarc retaining ring:: An internal or external circlip of rectangular cross section with holes for easier installation and removal

Truck:: A general term for a vehicle designed to haul something. The British term is lorry.
Also See:
articulated truck
breakdown truck
crew cab dump truck
flatbed truck
fork-lift truck
heavy-duty truck
lift truck
light-duty truck
light truck
medium-duty truck
tanker truck
utility truck

Truck camper:: A camping unit which mounts on the bed of a pickup truck. Also called "pickup camper," or "slide-on camper," "slide-in camper," or simply "camper." Usually the tailgate of the pickup is removed and the camper unit is clamped to the truck. They provide cooking facilities, a refrigerator, heater, air conditioner, a self-contained toilet, a fresh water tank, a waste water tank, a faucet, a sink, a LP (propane) gas supply, and a separate 100-125 volt electrical system. They can sleep from two to six people. Prices range from $5,000 to $30,000. Its advantage is that the vehicle can be used to drive into remote locations.

Trucker slang:: A colloquial set of expressions used on a CB communication device.

Truck, refrigerated:: Commercial vehicle equipped to maintain below-ambient temperatures,.

Truck tractor:: See tractor.

True:

Something that is accurately made or correctly adjusted.
To adjust something so that it is able to fit perfectly. Also see out of true

True up:: To dress

Truing:: The act of cutting rubber off the tread of a tire while rotating on a "truing" machine to make the tire assembly round. A sometimes harmful practice which takes off tread rubber to allow for an out of round wheel, or for a tire not mounted properly.

Trunion:: A British term for kingpin -- a mechanical pivot located at the lower end of the suspension wheel upright.

Trunk:: The storage compartment of a vehicle. In older cars, a large suitcase (or trunk) was strapped to the back of the vehicle. In rear-engine vehicles, the trunk is located in the front of the vehicle (e.g., Volkswagen); but generally it is located at the rear of the vehicle. Also see escape trunk

Trunk handle:: A lever or handle for opening the trunk

Trunk lid:: The cover of the trunk which is hinged

Trunk model:: A vehicle which may come as a hatchback or stationwagon is available in a style which has a trunk behind and below the backlight (i.e., rear window).

Trunk rack:

A luggage rack which is mounted to the surface of the trunk. Some are merely decorative.
A bicycle carrying attachment mounted by straps to the rear of a car or truck. Less expensive than most roof or hitch racks.

Trunk spoiler:: A rear spoiler which is mounted to the lid of the trunk.

Sign My Guestbook

View My Guestbook