TOLERANCE--The amount of variation permitted
THERMOSTATIC SWITCH--A switch that is
from an exact size or measurement; the actual
turned on or off by temperature change.
amount from smallest acceptable dimension to
THROTTLE--A mechanism in the fuel system that
largest acceptable dimension.
permits the driver to vary the amount of fuel-air
TORQUE--A force or combination of forces that
mixture entering the engine and thus control engine
produces or tends to produce a twisting or rotary
THROTTLE VALVE PLATE--The disk in the lower
TORQUE CONVERTER--A special form of fluid
part of the carburetor air horn that can be tilted to
coupling in which torque may be increased (at
pass more or less fuel-air mixture to the engine.
expense of speed).
THRUST BEARING--A bearing that is designed to
resist axial (sideways) forces of a rotating member.
to engine torque increase that occurs within a
THRUST--A force tending to push a body out of
alinement. A force exerted endwise through a
TORQUE ROD--An arm or rod used to ensure
member upon another member.
accurate alinement of an axle with the frame and to
TIE ROD--A rod connection in the steering system
relieve the suspension system springs of driving
and braking stresses.
TIMED FUEL INJECTION--Fuel injection system
TORSIONAL VIBRATION--Vibration in a rotary
that injects fuel on an individual cylinder basis and
direction; a portion of a rotating shaft repeatedly
in sequence with the cylinder's intake stroke.
moves ahead, or lags behind, while the remainder
TIMING--Refers to ignition or valve timing and
of the shaft is exhibiting torsional vibration.
pertains to the relation between ignition or valve
TORUS--The rotating members of a fluid coupling.
mechanism and piston position in the cylinder.
TRANSDUCER--A device that is actuated by power
TIMING BELT--A flexible toothed belt that, through
from one system and supplies power in another
sprockets, drives the engine camshaft.
form to a second system.
TIMING CHAIN--A link- or roller-type continuous
TRANSFER CASE--A gearbox, driven by the trans-
chain that, through sprockets, drives the engine
mission that will provide driving force to both front
and rear propeller shafts on four-wheel drive
TIMING GEARS--A pair of helical gears that drive
the engine camshaft.
TRANSMISSION BRAKE--A brake placed at the
TIMING MARKS--A pair of reference points that
rear of the transmission, usually used for parking.
are used to obtain correct timing of the valves or
TRANSMISSION--The device in the power train that
ignition distributor of an engine.
provides different gear ratios between the engine
TOE-IN--The number of inches that the front wheels
and driving wheels, as well as reverse.
of a vehicle point in toward the center of the
TRUNNION--Either of two opposite pivots or
vehicle. A measurement is obtained by measuring
the distances between the front tires at the forward
assembly, supported by bearings, to provide a
and rearward edges and taking the difference
means of swiveling or turning the part or assembly.
between the two dimensions. The measurements
TUBING--A type of fluid line whose dimensions are
are taken with the wheels in the straight ahead
designated by actual measured outside diameter
and by actual measured wall thickness.
TOE-OUT--The difference in turning of the inner
TURBINE--A rotary motor actuated by the reaction,
wheel, with the outer wheel turned at a 20-degree
impulse, or both, of a flow of pressurized fluid.
angle. The inner wheel must turn sharper than the
outer, the wheels are further apart at the forward
TURBINE ENGINE--An engine that uses the expan-
edge (toe) than the rearward edge.
sive force of burning gases to spin a turbine.