Glossary “radius arms” Definition:
Longitudinal suspension arms used to position a beam axle.
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radius plates
Glossary “radius plates” Definition:
Alignment gauge that fits under the front wheels and measures in degrees how far a wheel is turned to the right or left.
radiator shutter system
Glossary “radiator shutter system” Definition:
An engine temperature-control system that controls the amount of air flowing through the radiator by use of a shutter system. Used on HD trucks.
radio choke
Glossary “radio choke” Definition:
Small coil of wire installed in the power lead, leading to a pulsing unit such as an IVR to prevent radio noise ( reduce RFI).
radio frequency interference (RFI)
Glossary “radio frequency interference (RFI)” Definition:
Form of electromagnetic interference created in the ignition secondary circuit which disrupts radio and television transmission. In general, any cicuit that is opened and closed, causes some amount of RFI.
radiator core
Glossary “radiator core” Definition:
The center of the radiator, made of tubes and fins, used to transfer heat from the coolant to the air.
radiator core support
Glossary “radiator core support” Definition:
Framework around the front of the body structure for holding the cooling system radiator and related parts.
radiator fan
Glossary “radiator fan” Definition:
Term used for fan.
radiator hose
Glossary “radiator hose” Definition:
An oil and ozone resistant synthetic-rubber hose that connects the radiator to the thermostat outlet housing and water pump inlet housing.
radiator hose clamp
Glossary “radiator hose clamp” Definition:
Term used for hose clamp.
radiator pressure cap
Glossary “radiator pressure cap” Definition:
A cap that seals in pressure from hot expanding coolant until a predetermined limit is reached, then the valve opens, allowing excess pressure to escape, generally to a coolant-recovery tank.
radiator cooler
Glossary “radiator cooler” Definition:
Small reservoir located in the side or bottom of the radiator which is surrounded by cooling system coolant, though which transmission fluid is pumped in order that it can be cooled. Sometimes called an heat exchanger.
radiation
Glossary “radiation” Definition:
1). Process by which energy is transmitted. 2). The transfer of heat through a solid, liquid, or gas medium.
radiator
Glossary “radiator” Definition:
Heat exchanger used to remove heat from the coolant in the cooling system containing vertical or horizontal-finned tubing section connected between two tanks.
radiator cap
Glossary “radiator cap” Definition:
Term used for radiator pressure cap.
radiator cap pressure test
Glossary “radiator cap pressure test” Definition:
Test done with a cooling system pressure tester and cap adapter. The tester gauge should stop increasing its pressure reading when the cap rating is reached.
radial movement
Glossary “radial movement” Definition:
Horizontal movement.
radial ply
Glossary “radial ply” Definition:
Term used for radial ply belted tire.
radial ply belted tire
Glossary “radial ply belted tire” Definition:
A tire having the ply cords placed at right angles to the beads, plus belts under the tread section providing the least tread distortion while moving, thereby minimizing tread wear and rolling friction.
radial runout
Glossary “radial runout” Definition:
Variations in tire diameter; the measured amount of out-of-roundness on rotating tires.