80 entries found for U

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- U -


Uranium An element with the atomic number of 92.


U-shaped bolts to fit around the rear-axle housing for clamping the leaf spring to the housing.


A short term for universal joint.


A term used for manomometer.


An acronym for United States.




Universal Asynchronous Receive and Transmit. A type of data stream used on non-OBD-II diagnostic systems. UART toggles between 5 volts (positive) and 0 volts.


Utah Department of Transportation.


Universal ignition module.

Ultrahigh Frequency (UHF)

The band of signal frequencies falling between 300 and 3000 MHz.


An invisible spectrum with wavelengths shorter than visible light b longer than X-rays about 200 to 4000 angstrom units.

Ultraviolet Light

A light source used in non-destructive testing for cracks in metal parts.

Umbrella Seal

An umbrella-shaped valve stem seal used to direct oil away from the stem and guide.

Unburned Hydrocarbons

HC is a major pollutant in exhaust gases as a result of the partially unburned fuel after combustion.


An acronym for Unified National Coarse. Identifying a standard thread pitch and count.

Under-Dash Unit

A term used for hang on unit such as for a CB radio or other aftermarket accessory.

Under-Hood Lubrication Services

The work performed under the hood during a chassis lubrication such as lubricating the distributor, manifold heat-Control valve, upper suspension, hood hinges and latch, checking the fluid in the engine crankcase, brake master cylinder, radiator, battery, and power steering reservoir, plus inspecting belts and safety-related items.

Under-Vehicle Lubrication Services

Work performed under the vehicle during a chassis lubrication such as changing oil and filter, checking or changing transmission fluid, and gear oil or differential gear oil, lubricating the suspension and steering system, universal joints, clutch ans/or transmission linkage, front-wheel bearings, and inspection of safety-related items.


The chassis of a vehicle.


An air-conditioning system that is short of refrigerant, resulting in improper cooling.


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