- CL
-
- Acronym for Comfort Luxe as a designation for a vehicle which is more luxurious than an L but not quite as luxurious as a GL
- Acronym for Closed Loop
- Cladding
-
- A process of covering one material with another and gluing them together under high pressure and temperature.
- The outer body panels which are attached to the vehicle's frame.
- Excessive decorative elements applied to a vehicle.
- Claim
-
- A demand for reimbursement made by the customer for freight that is lost and/or damaged.
- A demand made by the customer for a refund on overcharge on transportation bill
- A demand made by an individual or company to recover loss under insurance policy.
- Clamp
- A fastening device which secures something within its jaws without constant human
pressure.
Also see
- Anchor Clamp
- Bar clamp
- Battery clamp
- C-clamp
- Cable clamp
- Cheney Clamp
- Distributor hold-down clamp
- G-clamp
- Hose clamp
- Hose clamp installer
- Hose clamp pliers
- Jubilee Clamp
- Locking bar clamp
- Locking clamp
- Long-reach C-clamp
- Piston ring clamp
- Screw Clamp
- Sheet metal clamp
- Triple clamp
- V-band clamp
- Welding clamp
- Wheel clamp
- Clamshell
- A shape which has a bottom and top but is hinged at one end so that it can be opened to expose its interior.
- Clapboard
- A narrow board which is thicker at one edge than the other edge and used to protect from the weather.
- Clarifier
- A machine used for a liquid-sludge separation in which the particles with a higher specific gravity are separated from the lower specific gravity of the liquid. A clarifier bowl has one outlet for the light phase oil; the heavier phase particles are retained on the bowl wall.
- Clark
- Clark, Jim -- Winner of 3 Formula One Championships, 25 Grand Prix races and of the 1965 Indianapolis 500
- Class 1 driver's license
-
In Canada, a driver's license which permits driving semi-trailer trucks and all other motor vehicles or combinations of vehicles except motorcycles

Semi-trailer truck
- Class 1 motor carrier
- A U.S. classification of a common or contract motor carrier with annual gross revenues of five million dollars or more.
- Class 1 road
- Hard surface highways including interstates and U.S. numbered highways (including alternates), primary state routes and all controlled access highways.
- Class 2 driver's license
-
In Canada, a driver's license which permits driving the following

Class 2
- Buses, including school buses, special activity buses and special vehicles
- Trailers or towed vehicles that do not exceed 4,600 kilograms except if the bus and trailers or towed vehicles do not have air brakes
- Any motor vehicle or combination of vehicles in Class 4
- Class 2 road
- Hard surface highways including secondary state routes, primary county routes and other highways that connect principle cities and towns, and link these places with the primary highway system.
- Class 3 driver's license
-
In Canada, a driver's license which permits operating the following

Class 3
- Trucks with more than two axles, such as dump trucks and large tow trucks, but not including a bus that is being used to transport passengers
- Trailers that do not exceed 4,600 kilograms except if the truck and trailers do not have air brakes
- A tow car towing a vehicle of any weight
- A mobile truck crane
- Any motor vehicle or combination of vehicles in Class 5
- Class 3 road
- Hard surface roads not included in a higher class and improved, loose surface roads passable in all kinds of weather. These roads are adjunct to the primary and secondary highway systems. Also included are important private roads such as main logging or industrial roads that serve as connecting links to the regular road network.
- Class 4 driver's license
-
In Canada, there are two types of Class 4 driver's license unrestricted and restricted The unrestricted Class 4 allows driving the following

Class 4
- Buses with a maximum seating capacity of 25 persons (including the driver), including school buses, special activity buses and special vehicles used to transport people with disabilities
- Taxis and limousines
- Ambulances
- Any motor vehicle or combination of vehicles in Class 5
The restricted Class 4 allows driving the following
Class 4
- Taxis and limousines (up to 10 persons including the driver)
- Ambulances
- Special vehicles with a seating capacity of not more than 10 persons (including the driver) used to transport people with disabilities
- Any motor vehicle or combination of vehicles in Class 5
- Class 4 road
- Unimproved roads that are generally passable only in fair weather and used mostly for local traffic. Also included are driveways, regardless of construction.
- Class 5 driver's license
-
In Canada, a driver's license which permits operating the following

Class 5
- Two axle vehicles including cars, vans, trucks and tow trucks
- Trailers or towed vehicles may not exceed 4,600 kilograms
- Motor homes (including those with more than two axles)
- Limited speed motorcycles or moped (in some provinces, a Class 8 is required to operate these) and all-terrain vehicles (ATVs)
- Passenger vehicles used as school buses with seating capacity of not more than 10 persons (including the driver)
- Construction vehicles
- Three-wheeled vehicles - does not include three-wheeled motorcycles (trikes) or motorcycle/sidecar combinations
- Does not include Class 4 vehicles or motorcycles
- Class 6 driver's license
-
In Canada, a driver's license which permits operating the following

Class 6
- Motorcycles, all-terrain cycles, all-terrain vehicles (ATVs)
- Class 7 driver's license
-
In Canada, a learner's driver's license which permits operating the following

Class 7
- Two axle vehicles including cars, vans, trucks and tow trucks
- Trailers or towed vehicles may not exceed 4,600 kilograms
- Motor homes (including those with more than two axles)
- Limited speed motorcycles and all-terrain vehicles (ATVs)
- Passenger vehicles used as school buses with seating capacity of not more than 10 persons (including the driver)
- Construction vehicles
- Three-wheeled vehicles - does not include three-wheeled motorcycles (trikes) or motorcycle/sidecar combinations
- Does not include Class 4 vehicles or motorcycles
- Class 8 driver's license
-
In some provinces of Canada, a driver's license which permits operating a moped or limited speed motorcycles

Moped
- Class 9 driver's license
-
In some provinces of Canada, a driver's license which permits operating a farm tractor

Class 9
- Class A driver's license
-

Class 1
- In some provinces of Canada, a driver's license which permits
operating
- Any tractor-trailer or combination of motor vehicle and towed vehicles where the towed vehicles exceed a total gross weight of 4,600 kilograms
- Any motor vehicle pulling double trailers
- Any motor vehicle pulling a trailer with air-brakes
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- A class A with restrictions prevents operating
- a motor vehicle pulling double trailers
- a motor vehicle pulling a trailer with air-brakes
- In some provinces of Canada, a driver's license which permits
operating
- Class A RV
-

Class A RV
The Class A is the largest and usually most luxurious motorhome. They are frequently constructed on custom undercarriages or on a 3-10 ton truck chassis. Many also feature an automatic slideout so that at the touch of a button, a portion of the RV exterior wall can extend outward to expand living space. Most models offer complete self-containment, with on-board generator, large water and holding tanks, big batteries and a generous propane supply. They usually provide cooking facilities, a refrigerator, heating, air conditioning, a self-contained toilet, water tanks (fresh water, grey water, black water), faucets, sinks, a LP (propane) gas supply, a separate 100-125 volt electrical system, and a full array of appliances and entertainment features. They are especially good for dry camping (without hookups), even for extended periods. They can sleep up to eight people, depending on the model and the floor plan. Prices range from $80,000 to above $700,000 for high end rear diesel models.
Class A RV
- Average weight 13,000 to 48,000 pounds
- Average Length 25 to 45 feet in overall length
- Average Height 10 feet high
- Class B driver's license
-
In some provinces of Canada, a driver's license which permits operating the following

Class B
- Any school purposes bus with designed seating capacity for more than 24 passengers
- Any regular bus with designed seating capacity for more than 24 passengers
- Any truck or motor vehicle combination exceeding 11,000 kg provided the towed vehicle is not over 4,600 kg
- School purposes bus - maximum of 24 passenger capacity
- Regular bus maximum of 24 passenger capacity and ambulances
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- Class B RV
-
A small motorhome usually called a van conversion or camping van conversion. The basic Class B RV is built on an ordinary van chassis which retains the original dimensions of the van but features a raised roof (usually fiberglass) in order to allow full standing headroom. They also include a small galley (cooking facility, refrigerator, heater, fresh water tank, waste water tank, faucet, sink), a LP (propane) gas supply, 110 Volt AC and 12 Volt DC electrical outlets, and portable toilet. They can sleep from two to four people.

Class B RV
- Average Weight 6,000 to 8,000 lbs
- Average Length 17 to 19 feet
- Average Height 7 to 8 feet
- Average Price $40,000 to above $100,000
- Class C driver's license
-
In some provinces of Canada, a driver's license which permits operating the following

Class C
- Any regular bus with designed seating capacity for more than 24 passengers
- Regular bus maximum of 24 passenger capacity and ambulances
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- Class C RV
-

Class C RV
A recreational vehicle (also called a mini-motorhome) built on a van chassis that has been cut just behind the cab (the driver's section) so that a camping unit can be attached to the rear. Generally these units are easier to drive than a Class A motorhome. They are generally constructed on a larger van chassis. The driver compartment is similar to a van, with a large box in the back. Class C motorhomes usually come with a sleeping bunk above the cab, in addition to a bedroom in the rear of the unit. Like their Class A big brothers, many Class C units feature a slideout to quickly extend the motorhome's living space. Class C units usually provide cooking facilities, a refrigerator, heating, air conditioning, a self-contained toilet, water tanks (fresh water, grey water, black water), faucets, sinks, a LP (propane) gas supply, a separate 100-125 volt electrical system, and a full array of appliances and entertainment features. Class C motorhomes can sleep up to ten people depending on the model and the floor plan.
Class C RV
- Average Weight 10,000 to 12,000 pounds
- Average Length 20 to 31 feet in length
- Average Height about 10 feet high
- Average Price $50,000 to around $150,000
- Class D driver's license
-
In some provinces of Canada, a driver's license which permits operating the following

Class D
- Any truck or motor vehicle combination exceeding 11,000 kg provided the towed vehicle is not over 4,600 kg
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- Class E driver's license
-
In some provinces of Canada, a driver's license which permits operating the following

Class E
- School purposes bus - maximum of 24 passenger capacity
- Regular bus maximum of 24 passenger capacity and ambulances
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- Class F driver's license
-
In some provinces of Canada, a driver's license which permits operating the following

Class F
- Regular bus maximum of 24 passenger capacity and ambulances
- Any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.
- Class G driver's license
-
In some provinces of Canada, a driver's license which permits operating any car, van or small truck or combination of vehicle and towed vehicle up to 11,000 kg provided the towed vehicle is not over 4,600 kg.

Class G
- Classic car
-
- An older vehicle that is generally considered to be one of the finest models ever built. As used by the average person, an older vehicle in original (like-new) shape or has been restored with some modern refinements (e.g., special wheels, improved seating, modified engine, 12-volt electricals, etc.)
- A vehicle (including hardtop or convertible) built during 1950-1973 and in original form with no modern technology, equipment, or refinements except wheels.
- A vehicle defined by the Classic Car Club of America built during the years 1925-1948. They include the following:
- A.C. (all 1925-40)
- Adler (1928-1934 Standard 8)*
- Alfa-Romeo
- Alvis (Speed 20, 3.5 litre, 25, and 4.3 litre)
- Amilcar*
- Armstrong-Siddeley (1924-1933 Model 30, 1933-1939 Special)
- Aston-Martin (1927 -1939 - All)*
- Auburn (All 8 and 12 cylinder)
- Austro-Daimler
- Ballot (2LS, 2LT, 2LTS, RH, RH2, and RH3)*
- Bentley (All from 1919)
- Benz (1925 and 1926, 10/30,11/40, 16/50 and 16/50 Sport)*
- Blackhawk
- BMW (327, 328, 327/328, 335)
- Brewster (All 1934-1936, All Heart Front)*
- Brough Superior*
- Bucciali (TAV 8, TAV 30, TAV 12 and Double Huit)*
- Bugatti (All except types 52 and 68)
- Buick (1931-32 series 90 and Limited)*
- Cadillac (1925-35, all 12-cyl and 16-cyl, 1938-47 60 Special, 1936-48 all series 63, 65, 67, 70, 72, 75, 80, 85, 90, all V-63 from 1923, 1940-47 all 62 Series)
- Chenard-Walcker*
- Chrysler (1926-32 Imperial and Series 80. Includes Series CG, CH, CL; 1932 - 1939 Custom Imperial Series - CL, CX, CW, C-3, C-11, C-15, C-20, C-24; 1940 - 1948 Crown Imperial - Includes Series C-27, C-33, C-37, C-40; Newports and Thunderbolts)
- Cord
- Cunningham (All V Series from 1916)
- Dagmar (6-80)
- Daimler (All 8 and 12 cylinder, 1925-1934 6 cylinder, 3 1/2 litre and larger models: 25, 25/85, 20/25, 20/30 (1925-1934); 30 (1925); 30, 35/120 (1925-1932); 45 (1925-1926).)*
- Daniels (1920-1926 8 cylinder Model D)
- Darracq (8-cyl. cars and 4-litre, 6-cyl. cars only)
- Delage (Model D-8, not 4-cyl.; 1924-1926 GL and GLS Models)*
- Delahaye (Series 135, 145, 148, 165 not 4-cyl.)*
- Delaunay Belleville (6-cyl. cars only)
- Doble
- Dorris
- Duesenberg (All from 1921)
- DuPont
- Elcar (1925 - 1933 Models: 8-80, 8-81, 8-90, 8-91, 8-92, 120, 130 and 140)
- Excelsior*
- Farman (All 1920 - 1931)*
- Fiat*
- FN*
- Franklin (All models except 1933-34 Olympic Six)
- Frazer Nash*
- Georges Irat
- Graham (1929-1931 Series 127; 1930 -1931 Series 137)
- Graham-Paige (1929-1931 Series 827; 1928-1929 Series 835; 1929 -1930 Series 837)*
- Hispano Suiza (H6 from 1919, All French models, Spanish models T56, T56BIS, T64)
- Horch
- Hotchkiss*
- Hudson (1929 Series L)
- Humber*
- Invicta (All through 1938)
- Isotta-Fraschini (All from 1919 except Tipo 8C Monterosa)
- Itala
- Jaguar (1946-48 2.5 Litre, 3.5 Litre Mark IV, not 4-cyl.)
- Jensen (1936-1939 All except 2 1/4 Litre 1645)*
- Jordan (1929 - 1931 Models G, 90, Great Line 90, Speedway Series 'Z')
- Julian*
- Kissel (6-55 from 1923, 1925-1926, 1927 8-75, 1928 8-90 and 8-90 White Eagle, 1929-1930 8-95 White Eagle, 1929-1931 8-126)
- Lagonda (All models through 1940 except 1934 - 1940 Rapier Two Post-War V-12)
- Lanchester (1919 - 1931 models 21, 23, 30 and 40)*
- Lancia*
- LaSalle (All 1927-1933)
- Lincoln (All 1920 through 1940 models L, KA, KB, and K; 1941 - 168 H; 1942 - 268 H)
- Lincoln Continental
- Locomobile (All left hand drive models 48 from 1914 and all model 90, 1927 - 1929 Model 8-80, 1929 Model 8-88)
- Marmon (All 16-cyl.; 1925-26 74; 1927 75; 1928 E75; 1930 Big 8; 1931 88 and Big 8)
- Maserati*
- Maybach
- McFarlan (TV6 and 8)
- Mercedes*
- Mercedes-Benz (All 230 and up, and K, S, SS, SSK, SSKL, Grosser and Mannheim)*
- Mercer
- M.G. (1935-39 SA, 1938-39 WA)*
- Minerva (All except 4-cyl)
- Moon (Custom bodies only)*
- N.A.G.*
- Nash (1930 Series 490, 1931 Series 890, 1932 Series 990 and 1090, 1933 Series 1190, 1934 Series 1290, 1940 Sakhnoffsky Special Cabriolet)*
- Packard (All 12 cylinder models 1932 through 1939; 1923-1924 Models 226 and 233; All 1st Series 8 cylinder; 1925 - 1934 All sixes and eights; 1935 Models 1200 - 1205, 1207 and 1208; 1936 Models 1400 - 1405, 1407 and 1408; 1937 Models 1500 - 1502 and 1506 - 1508; 1938 Models 1603 - 1605, 1607 and 1608; 1939 Models 1703, 1705, 1707, and 1708; 1940 Models 1803, 1804, 1805, 1806, 1807, and 1808; 1941 Models 1903, 1904, 1905, 1906, 1907, and 1908; 1942 Models 2023, 2003, 2004, 2005, 2055, 2006, 2007, and 2008; 1946 - 1947 Models 2103, 2106 and 2126; All Darrin-bodied)*
- Peerless (1925 Series 67; 1926 - 1928 Series 69; 1930 - 1931 Custom 8; 1932 Deluxe Custom 8)
- Peugeot*
- Pierce-Arrow (1921 Series 32, 1922 and up Series 33, All from 1925)
- Railton*
- Raymond-Mays*
- Renault [45 HP (40 CV) to 1928, 40 hp (41CV) Reinastella, Reinasport, 1929-1934; Nervahuit, Nervastella, Nervasport, Suprastella 8 cylinder models 1930-1939]*
- Reo (1931-33 Royale 8-31, Royale 8-35, Royale 8-52, and Royale Custom 8 and 1934 N1, N2, and 8-52)
- Revere
- Riley*
- Roamer (All Rochester-Duesenberg 4-cylinder, 1925 6-54E, 1925-1929 8-88, 1929-1931 8-125)
- Rochet-Schneider*
- Rohr
- Rolls-Royce (All from 1919)
- Ruxton
- Squire
- SS and SS Jaguar (1932 - 1940 S.S. 1, S.S. 90, SS Jaguar, and SS Jaguar 100)
- Stearns-Knight
- Stevens Duryea
- Steyr*
- Studebaker (1928 8, FA and FB President, 1929 - 1933 President except Model 82)
- Stutz
- Sunbeam Talbot [8 cylinder and 3 litre twin cam (GB) 105 and 110(8-cyl. and 3-litre twin-cam only)]
- Talbot (all 105C and 110C)
- Talbot Lago (8-cylinder 1930-1935, 4 Litre 6-cylinder 1936-1939, 4 1/2 Litre 1946-1948)
- Tatra*
- Triumph (Dolomite 8 and Gloria 6 models only)
- Vauxhall (25-70 and 30-98 only)
- Voisin
- Wills Sainte Claire (All from 1921)
- Willys-Knight (Series 66, 66A, 66B Custom bodied only)*
- Classic Car Club of America
- (CCCA) Organization which defines which cars are true classics. 1645 Des Plaines River Road, Suite 7A, Des Plaines, IL, 60018-2206, ph 847.390.0443
- Classification society
- Independent and reputable organizations which verifies and inspects vessels for seaworthiness. As technical experts, they serve to provide the necessary basis for adjusting insurance rates for the vessel.
- Class M driver's license
-
In some provinces of Canada, a driver's license which permits operating one or more of the following

Class M
- Motorcycles
- limited-speed motorcycle (motor scooter)
- motor-assisted bicycle (moped)
- Class of Thread
- Threads differ by the amount of tolerance or tolerance and allowance specified. Classes 1A, 2A, and 3A apply to external threads, and Classes 1B, 2B and 3B apply to internal threads.
- Class rate
- A shipping term for the fees charged for commodities grouped according to similar shipping characteristics.
- Clay model
- When the design department is creating a new model, it will be built in clay to full size to determine its looks etc.
- Clean Air Act
- (CAA) In the U.S., the fundamental legislation to control air pollution. The original Clean Air Act was signed in 1963. The law set emissions standards for stationary sources, such as factories and power plants. Criteria pollutants included lead, ozone, CO, SO2, NOx and PM, as well as air toxics. The CAA was amended several times, most recently in 1990 (P.L. 101-549). The Amendments of 1970 introduced motor vehicle emission standards for automobiles and trucks. In 1990, reformulated gasoline (RFG) and oxygenated gasoline provisions were added. The RFG provision requires use of RFG all year in certain areas. The oxygenated gasoline provision requires the use of oxygenated gasoline during certain months, when CO and ozone pollution are most serious. The regulations also require certain fleet operators to use clean-fuel vehicles in 22 cities.
- Clean Air Act Amendments of 1990
- This legislation to improve the quality of the atmosphere and curb acid rain promotes the use of cleaner fuels in vehicles and stationary sources.
- Clean Development Mechanism
- (CDM) A Kyoto Protocol program that enables industrialized countries to finance emissions-avoiding projects in developing countries and receive credit for reductions achieved against their own emissions limitation targets.
- Clean diesel fuel
- An evolving definition of diesel fuel with lower emission specifications, which strictly limit sulfur content.
- Clean Fuel
- The CAA (as amended in 1990) specification that identifies RFG and alternative fuels as clean fuel.
- Clean-Fuel Fleet Program
- Federal program requiring fleet purchase of Clean-Fuel Vehicles beginning in 1988.
- Clean-Fuel Vehicle
- (CFV)A vehicle that has been certified by the EPA to meet the clean-fuel standards of the Clean Air Act Amendments of 1990. The three categories of federal CFV standards from least to most stringent are LEV, ULEV, and ZEV. The ILEV standard is voluntary and does not need to be adopted by states as part of the Clean-Fuel Fleet Program. CFVs are eligible for two federal programs, the California Pilot Program and the Clean-Fuel Fleet Program. CFV exhaust emissions standards for light-duty vehicles and light-duty trucks are numerically similar to those of CARB's California Low-Emission Vehicle Program.
- Clean oil lubrication
- A lubrication system where fresh oil is supplied to the engine as needed -- such as in a two-stroke engine.
- Clean shot
- Trucker slang for "No highway patrol around" as in "Large Car you got a clean shot all the way to the state line."
- Clearance
- A given amount of space between two parts such as between Piston and Cylinder, bearing and Journal , etc.
- Clearance fit
- Parts that are assembled so that there is clearance between them so that one part can slide in or on the other. Also called sliding fit
- Clearance height
-
- The distance between the ground and the lowest portion of the bottom of a vehicle (not counting the wheels). Also called ground clearance.
- The distance between the top of a vehicle and the bottom of a bridge or tunnel which determines whether the vehicle can pass under it.
- Clearance lamp
- A light which is mounted on the extreme edges of the roof of a truck to show the maximum height and width of a vehicle. Also called marker lamp.
- Clearance pocket compressor
- Small space in a cylinder from which compressed gas is not completely expelled. This space is called the compressor clearance space or pocket. For effective operation, compressors are designed to have as small a clearance space as possible.
- Clear flood mode
- A situation in which a carburetor or fuel injection system increases the amount of air or reduces the amount of fuel when necessary to correct a problem of Flooding.
- Clear lacquer
- A paint finish or sealer that is "crystal-clear" transparent, durable, dries rapidly, and usually does not require sanding.
- Cleat
-
- An attaching bracket
- Clips at intervals on the horizontal stiffeners of hatch coamings to secure the hatch covers
- A fitting with two prongs which is attached to the wall of a cargo ship or trailer so that one end of a rope or strap could be knotted and the other end secures the shipment or the shipping mats or battens in place. Also called a kevel.
Also see
- CLEPA
- Acronym for Comité de Liaison de la Construction d'Equipements et de Pièces d'Automobiles (i.e., European Association of Automotive Suppliers).
- Clevis
- A U-shaped metal piece with holes in each end through which a pin or bolt is run, used for attaching the brake pedal to the power brake booster pushrod, the clutch pedal to the clutch cable or master cylinder pushrod and for various other connections on an automobile. Clevises are sometimes used in other parts of the brake system, like attaching the parking brake cable to the parking brake lever at the rear brakes
- Clevis pin
-
A cylinder with a head at one end and a hole at the other. When the clevis pin is inserted into a hole, the head prevents it from going all the way through. A Cotter pin or Hitch pin clip is inserted in the other end of the clevis pin to keep it secure.

Clevis pin
- Click
-
- The action of inserting a bicycle shoe's bracket into the receiving part of a click-in pedal (formerly known as a clipless pedal).
- A colloquial term for a Kilometer
- Click-in pedals
-
A term for road bike pedals that use a releasable mechanism like that of a ski binding to lock onto cleated shoes and do not use toe clips or straps. Replaces the term Clipless pedals. Some brands are SPD, Look, Time, and Speedplay.

Click-in Pedal
- Click-type torque wrench
- A torque wrench which gives out an audible click when the preset torque is reached.
- Climate change
-
- The international concern that increasing concentrations of greenhouse gases (GHGs) in the atmosphere are changing the climate in ways detrimental to our social and economic well-being.
- A term used to refer to all forms of climatic inconsistency, but especially to significant change from one prevailing climatic condition to another. In some cases, climate change has been used synonymously with the term global warming; scientists, however, tend to use the term in a wider sense inclusive of natural changes in climate, including climatic cooling.
- Climate control
-
- A lever or button which you can move to change the temperature in the passenger compartment of a vehicle. It controls the heater, vent, and/or air conditioner.
- A space in which an ideal climate is maintained by some devices.
Also see
- Climatic chamber
- A test area into which an automobile can be placed to see if it will meet the extremes of temperature and humidity.
- Climbing ability
- While some vehicles may have a high top end speed on a road with no incline, the real test of a vehicle in mountainous terrain is its ability to go up a hill at an adequate speed (i.e., its climbing ability).
- Clincher
- A tire whose edges hook under the curved-in hooked edge of a special rim, not commonly found anymore on Bicycles and often confused with the common Wired-on tire.
- Clincher tire
- A tire whose edges hook under the curved-in hooked edge of a special rim, not commonly found anymore on Bicycles and often confused with the common Wired-on tire.
- Clinch nut
- A nut having a pilot which, after insertion in a hole, is clinched or staked in place to prevent rotation.
- Clinker
- Powdered cement, produced by heating a properly proportioned mixture of finely ground raw materials (calcium carbonate, silica, alumina, and iron oxide) in a kiln to a temperature of about 1480°C.
- Clip
-
- To move at a fast pace
- The removable front end of a vehicle, usually one designed for racing.
- A securing fastener
- Clipless pedals
-
An obsolete term for road bike pedals that use a releasable mechanism like that of a ski binding to lock onto cleated shoes and do not use toe clips or straps. Preferred term is Click-in pedals. Some brands are SPD, Look, Time, and Speedplay.

Clipless pedal
- Clip-ons
-
- Low racing handlebars for a motorcycle that clamp directly onto the fork legs
- Handlebars that attach directly to the fork tubes, rather than to the top yoke, that hold the fork tubes together
- Clip-on weight
- A wheel weight that is clipped on the rim between the rim and the tire. It is used to balance a wheel.
- Clock
-
- An instrument showing the time.
- An odometer as in the statement I want to buy this car, but it has too many miles on the clock.
- To record the speed or time that vehicle makes.
- To turn the odometer back (an illegal practice)
Also see
- Clocking
-
- The action of recording the speed of a vehicle.
- In Britain, it is the action of turning the odometer back.
- Clockwise
- Rotation to the right like the direction of clock hands. In most cases it is the direction to secure a nut to a bolt. It is the opposite to Counterclockwise.
- Clog
- To obstruct a passageway or track so that the normal flow or operation of something is hindered.
- Close-coupled sedan
- Similar to the Sedan, this body style is shorter and thus usually accommodates only five passengers. The rear quarter windows were eliminated.
- Closed container
- Container sealed by means of a lid or other device so that neither liquid nor vapor will escape from it at ordinary temperatures.
- Closed crankcase ventilation
- A system in which Crankcase vapors are discharged into the engine Intake system (usually through the Intake manifold) and pass through the engine Cylinders rather than being discharged into the atmosphere.
- Closed Distribution System
- A shipping system confined to moving goods between specified plants and facilities.
- Closed-end connector
- Solderless connector shaped like a hat. Used to join two, three, or more wires together. Similar to wire connectors used in home wiring, but installed by crimping instead of twisting
- Closed end lease
- Most leases offered today are close-end leases, meaning that the residual value is fixed and stated in the lease contract. The lessee's financial obligations are unaffected by what the vehicle is actually worth when the lease ends. In other words, the lessee assumes no risk for the depreciation of the vehicle.
- Closed loop
-
- An operating condition or mode which enables modification of programmed instructions based on a feedback system
- A condition, after the appropriate sensors have indicated that predetermined conditions have been met, where the computer actively controls the fuel system and other functions based on exhaust gas conditions and other parameters.
- The repeated times when the EFI computer uses the feedback on the mixture provided by the oxygen sensor to control the injected amounts of fuel.
- Closed-Loop Carburetion
- System in which the fuel/air ratio in the engine is carefully controlled to optimize emissions performance. A closed-loop system uses a fuel metering correction signal to optimize fuel metering.
- Closed loop fuel control
- The normal operating mode for a feedback carburetor system. Once the engine is warmed up, the computer can interpret an analog voltage signal from an exhaust gas oxygen sensor and alter the air/fuel ratio accordingly with a duty-cycle solenoid or solenoid-controlled valve.
- Closed loop mode
- Once the engine has reached warm-up temperature, the engine management computer collects the precise data from all the sensors (coolant temperature sensor, throttle position sensor, oxygen sensor, etc.) to determine the most efficient air/fuel mixture for combustion.
- Closed loop system
-
- A self-adjusting system which keeps conditions stable and is controlled by negative Feedback from a sensor.
- A computer controlled system which monitors the exhaust gas with a sensor and adjusts the fuel delivery, and may or may not adjust spark timing, transmission, and other devices to meet emission and driveability criteria
- Closed system
- An anti-lock brake system with some means, generally a pump, to restore hydraulic pressure that's bled off during an ABS stop
- Closer
- Usually a pushy salesman who is assigned to convince a hesitating customer to make the purchase of a vehicle when the original salesman can't make the sale.
- Close-ratio gearbox
- A transmission in which there is very little difference between one gear ratio and the next. This kind of transmission makes it easy for fast shifting.
- Closing cam
- A cam or rocker which closes a valve in a mechanically operated valve system. Other types close the valve through the operation of the valve spring. Also called closing rocker.
- Closing rocker
- A cam or rocker which closes a valve in a mechanically operated valve system. Other types close the valve through the operation of the valve spring. Also called closing cam.
- Cloud point
- (CP)
- The temperature at which Diesel oil tends to thicken and cloud up (i.e., become cloudy).
- A measure of the ability of a diesel fuel to operate under cold weather conditions. Defined as the temperature at which wax first becomes visible when diesel fuel is cooled under standardized test conditions.
- Cloverleaf
- A highway overpass system which has four basic loops for getting on the highway or leaving it.
- Club
-
A security device which surrounds the steering wheel making it difficult for a thief to operate the steering wheel.

Club
Also see
- Club Cab
-
A type of pickup truck (by Dodge) which has a second row of seating; but unlike a crew cab (which has four full size doors) it has a half-door that can be opened only after the main door is opened. The seating is usually a little more cramped than in a crew cab. Also called Extended Cab, King Cab, XtraCab, Access Cab, SuperCab, or Cab Plus.
Club Cab
- Club coupe
-
The club coupe designation seems to come from club car, describing the lounge (or parlor car) in a railroad train. The early postwar club coupe combined a shorter-than-sedan body structure with the convenience of a full back seat, unlike the single-seat business coupe. That name has been used less frequently in the 1976-86 period, as most notchback two-door models (with trunk rather than hatch) have been referred to as just coupes. Moreover, the distinction between two-door coupes and two-door sedans has grown fuzzy.

Club Coupe
- Club hammer
- A hammer with a short handle but a large, heavy head. It is used to hit the back end of a chisel or drift.
- Cluster gear
- The cluster of gears that are all cut on one long gear blank. The cluster gears ride in the bottom of the Transmission. The cluster provides a connection between the transmission Input shaft and the Output shaft. Also called Counter gear.
- Cluster panel
- The reverse side of the Instrument panel or Dash where all the wiring or circuit board is located.
- Clutch
-
- An electrically operated coupling device that connects or disconnects the compressor pulley and compressor shaft
- A device that disconnects the engine from the Transmission, to allow the vehicle to change gears, and then allows the engine and transmission to resume contact and turn together at a new Speed.
Also see- Band Clutch
- Block Clutch
- Center the clutch
- Centrifugal clutch
- Clutch diaphragm spring
- Clutch disc
- Clutch explosion
- Clutch housing
- Clutch lever
- Clutch pedal free travel
- Clutch pedal
- Clutch pilot bearing
- Clutch pressure plate
- Clutch semi-centrifugal release fingers
- Clutch shaft
- Clutch solenoid
- Clutch throwout fork
- Coil spring clutch
- Cone clutch
- Diaphragm spring clutch
- Diaphragm clutch
- Disengage the clutch
- Dog clutch
- Double clutching
- Dry clutch
- Electromagnetic clutch
- Fan clutch
- Fluid clutch
- Freewheeling
- Friction clutch
- Heavy clutch
- Hydraulically-activated clutch
- Hydraulically-assisted clutch
- Light clutch
- Lock-up clutch
- Magnetic clutch
- Multi-plate clutch
- Multiple-plate clutch
- Multiple disc clutch
- One way clutch
- Overrunning clutch starter drive
- Overrunning clutch
- Pull-type clutch
- Push-type clutch
- Reverse clutch
- Riding the clutch
- Roller clutch
- Single-plate clutch
- Slip the clutch
- Sprag clutch
- Stator roller clutch
- Torque converter lock-up clutch
- Twin-plate clutch
- Wet clutch
- Clutch aligning set
- A group of tools used to align the clutch plates with the flywheel. Usually there is a shaft, pilot bearing adapters, and tapered universal sleeves
- Clutch aligning tool
- A tool which looks like a bar or a disc which can be used to line up the clutch plates with the flywheel.
- Clutch antirattle spring clip
-
A specially shaped wire that prevents the clutch plate and spring from making noise when no pressure is applied to the plate.
Antirattle spring
- Clutch brake
- A device for slowing down the clutch discs (and thus the gears themselves) so that shifting is smoother and quieter.
- Clutch cable
- A cable (usually a cluster of thin strands within a plastic sheath) which operates the movement of the clutch plates. At the other end is a pedal (in automobiles) or a handlebar lever (left side).
- Clutch cycling switch
- A device that turns the compressor on and off in response to changes in pressure or evaporator temp
- Clutch diaphragm spring
-
A round dish-shaped piece of Flat spring steel. It is used to force the Pressure plate against the Clutch disc in some Clutches.
Clutch diaphragm spring
- Clutch disc
-
A spinning plate located at the end of the Driveshaft facing the engine Flywheel and covered with a Friction material such as Asbestos. When the Clutch is engaged, the disc is squeezed between the Flywheel and the Clutch pressure plate, causing the engine and the Transmission to turn at the same Speed. British term is called clutch plate.
Clutch disc
- Clutch drag
- When the clutch discs do not disengage completely after the clutch pedal is depressed or the clutch lever is pulled in, there is excessive friction so that it is difficult to shift gears because both the driven discs and the input shaft are both rotating.
- Clutch explosion
- Clutches have literally flown apart (exploded) when subjected to high rpm, a Scatter shield is used on competition cars to protect the Driver and spectators from flying parts in the event the Clutch explodes.
- Clutch field
- A clutch part on an air condition compressor, consisting of hundreds of windings of wire, that creates a magnetic field when current is applied, pulling in the armature to engage the clutch
- Clutch fork
- When the clutch pedal (or lever) is depressed, it pulls on a cable which moves the clutch fork which in turn pushes on the release bearing and disengages the clutch discs. Also called Clutch release fork.
- Clutch housing
- A Cast iron or Aluminum Housing that surrounds the Flywheel and Clutch mechanism. Also called Bell housing.
- Clutch interlock switch
- A switch that prevents the vehicle from starting unless the clutch pedal/lever is pressed.
- Clutch lever
- A hand-operated blade located on the left side of the
Handlebar of a
Motorcycle. When the clutch lever is pulled in, it
disengages the clutch so the engine and the Crankshaft
can turn independently of the Transmission and the
rider can change gears.
Also see
- Clutch, magnetic
- Clutch built into automobile compressor flywheel. operated magnetically. which allows pulley to revolve without driving compressor when refrigerating effect is not required.
- Clutch pedal
- A foot-operated pedal located on the floor of the vehicle to the left of the Brake pedal on cars with Manual transmission. When the clutch pedal is depressed, it disengages the clutch so the engine and the Crankshaft can turn independently of the Transmission and the Driver can change gears.
- Clutch pedal free travel
- The specified distance that the Clutch pedal may be depressed before the throwout bearing actually contacts the clutch release fingers.
- Clutch pilot bearing
- A small Bronze Bushing, or in some cases a Ball bearing, placed in the end of the Crankshaft or in the center of the Flywheel depending on the vehicle, that is used to support the outboard end of the Transmission Input shaft.
- Clutch pressure plate
-
That part of a Clutch assembly that through spring pressure, squeezes the Clutch disc against the Flywheel thereby transmitting a driving force through the assembly. To disengage the Clutch, the pressure plate is drawn away from the Flywheel via Linkage.
Clutch Pressure Plate
- Clutch pulley
- The clutch part turned by the drivebelt. The pulley or rotor free-wheels until the clutch is engaged. On rotors which contain the field, the electrical connection is made through brushes similar to alternator and starter motor brushes
- Clutch release finger
- A flat piece of metal shaped like a curved finger. Through the movement of the throwout fork, the throwout bearing pushes against the clutch release fingers or levers to release pressure against the Pressure plate. Also called clutch release lever.
- Clutch release fork
-
A lever attached to the clutch throw-out bearing. When the fork presses the throw-out bearing against the center of the conical diaphragm spring, it pops inward, releasing the pressure plate from the flywheel and freeing the clutch disc so that the engine can turn without driving the transmission.
Clutch Release Fork
- Clutch rotor
- The clutch part turned by the drivebelt. The pulley or rotor free-wheels until the clutch is engaged. On rotors which contain the field, the electrical connection is made through brushes similar to alternator and starter motor brushes
- Clutch semi-centrifugal release fingers
- Clutch release fingers that have a weight attached to them so that at high rpm the release fingers place additional pressure on the Clutch pressure plate.
- Clutch shaft
- The shaft that takes power from the clutch into the Gearbox. Also called the Drive pinion.
- Clutch shudder
- When the clutch tries to engage (when the pedal or lever is released), but the discs do not mate securely, the discs engage intermittently and slip past each other making a noise like a shudder. In Britain, it is called clutch judder.
- Clutch slip
- Clutch slip occurs when the clutch tries to engage (when the pedal or lever is released), but the discs do not mate securely.
- Clutch solenoid
- In some automotive Air conditioners, a Solenoid that operates a clutch on the Compressor drive Pulley. When the Clutch is engaged, the Compressor is driven and cooling takes place.
- Clutch spring
- The clutch cover will have several posts over which the clutch spring (shaped like a cylinder) fits and pushes the pressure discs against the driven clutch discs to transmit power.
- Clutch throw-out bearing
-
A part of the Clutch activated by the Clutch pedal that allows the Clutch to disengage. If you allow the vehicle to Idle in gear with the Clutch pedal depressed, instead of shifting to Neutral gear, you can wear out the throwout bearing. The British term is Clutch release bearing.
Throw-out bearing
Also see
- Clutch throwout fork
- The device or fork that straddles the throwout bearing and that is used to force the throwout bearing against the clutch release fingers.
- Cluttered engine compartment
- An engine compartment or bay in which all the available space around the engine is occupied by other objects (alternator, pumps, air intake system, battery, wiper motor, heater motor, windshield washer motor, starter, radiator, air conditioner, hoses, pipes, wiring, electronic boxes, etc.)

