Final Spring PT.2
Air disc brakes use _________, which dissipates heat faster than drum brakes A ) vented rotors B ) two pistons C ) wear sensors D ) a single actuator
A
Air disc brakes use _________, which dissipates heat faster than drum brakes. A) vented rotors B) two pistons C) wear sensors D) a single actuator
A
Air is pulled into the compressor cylinders through the air intake valves during the piston downstroke also called ________ A) loading B) uncoupling C) coupling D) unloading
A
Air is pulled into the compressor cylinders through the air intake valves during the piston downstroke also called _________ A) loading B) uncoupling C) coupling D) unloading
A
Air pressure from the foot valve (signal air) is supplied to a service-control port on the ________ valve. A) relay B) proportioning C) quick-release D) service brake control
A
All wheel nuts must be tightened to the correct torque and in the proper __________ A ) sequence B ) alignment C ) clamping force D ) direction
A
Another name for a limiter valve is a(n) _______ valve. A) ratio B) inversion C) spring brake relay D) supply
A
Brake drum mounting holes and pilot surface must be ________ A) round and concentric B) matched correctly with its proper hub C) balanced D) cut to length
A
Brake temperatures can climb as high as _______ A) 1,000°F (538°C) B) 600°F (316°C) C) 650°F (343°C) D) 300°F (149°C)
A
Brake temperatures can climb as high as ________A ) 1,000 ° F ( 538 ° C ) B ) 600 ° F ( 316 ° C ) C ) 650 ° F ( 343 ° C ) D ) 300 ° F ( 149 ° C )
A
For what air brake system component would the following complaint apply? Won't pass air to unloader to "cut-off" compressor. A) Governor B) Relay valve C) Service brake chamber D) Air gauge
A
The _________ spring in the dual chamber actuator supplies the force used by the park/emergency brake circuit to hold the truck/trailer or tractor if air pressure is lost. A) power B) governor C) pressure D) graduating
A
The limiting factor to an air compressor's size is its expected _______ A) duty cycle B) maximum air pressure C) capacity D) minimum air pressure
A
The limiting factor to an air compressor's size is its expected _________ A) duty cycle B) maximum air pressure C) capacity D) minimum air pressure
A
What color is the octagonal-shaped trailer supply valve used to control the tractor protection system? A) Red B) Blue C) Green D) Yellow
A
What is a leading cause of premature wheel seal failures ? A ) Installation errors B ) Excessive preload C ) End play errors D ) Excessive tightening
A
What is the first reservoir receiving air from the compressor? A) Supply B) Safety C) Primary D) Secondary
A
What kind of lining is considered superior in heavy - duty applications because it is mechanically held to the shoe ? A ) Riveted B ) Heated C ) Bolted D ) Glued
A
What kind of lining is considered superior in heavy-duty applications because it is mechanically held to the shoe? A) Riveted B) Heated C) Bolted D) Glued
A
What type of hubs use manually adjusted wheel bearing end play ? A ) Standard B ) Preset C ) Unitized D ) Full floating
A
What type of valve is used to control spring brake operation in the park/emergency circuit of straight trucks the spring brake relay valve? A) Inversion B) Quick-release (QR) C) Proportioning D) Limiter (ratio)
A
What type of valve removes water and oil that may contaminate supply system air? A) Drain B) Pressure protection C) Inlet pressure regulating D) Turbocharger cut-off
A
What type of valves are critical devices used to speed up the flow of air during brake applications and release? A) Relay B) Exhaust C) Air brake D) Anti-compounding
A
What types of drums are bolted to the hub ? A ) Cast - spoke B ) Outboard C ) Hub - piloted D ) Stud - piloted
A
Wheel end play is the free movement of the wheel hub assembly along the ________ A ) axle spindle axis B ) axle housing C ) wheel's centerline D ) drive axle
A
When a brake chamber uses only a single chamber , it is called a _________ chamber . A ) service B ) long stroke C ) emergency spring brake D ) rear brake
A
When rims are installed on spoke wheels , which of the following needs to be checked and adjusted ? A ) Lateral run - out B ) Wheel bearings . C ) Radial run - out D ) Wheel bearing end play
A
When rims are installed on spoke wheels , which of the following needs to be checked and adjusted ? A ) Lateral run - out B ) Wheel bearings C ) Radial run - out D ) Wheel bearing end play
A
Which of the following are the most common foundation brakes found on heavy trucks today ? A ) Cam brakes B ) Hydraulic brakes C ) Air disc brakes . D ) Wedge brakes
A
Which of the following are the most common foundation brakes found on heavy trucks today? A) Cam brakes B) Hydraulic brakes C) Air disc brakes D) Wedge brakes
A
Which of the following causes shoe - drum friction to rotate the brake shoe into the drum with more force ? A ) Self - energization B ) Jackknifing C ) Cam - opposite positioning D ) Vibration
A
Which of the following is identified by the sudden exhaust of air draining from the dryer? A) Purging B) Unloading C) Snubbing D) Burnishing
A
Which of the following is the edge of the rim that creates a seal between the tire bead and the wheel ? A ) Bead seat B ) Rim flange C ) Rim diameter D ) Dynamic seal
A
Which valves distribute air to the brake chambers and control the air pressure supplied for braking? A) Foot brake B) Quick-release C) Relay D) Proportioning
A
Another term for brake application force is ________ pressure . A ) air B ) actuation C ) hydraulic D ) output
B
Brake drums need to be discarded if they experience __________ A) poor lining-to-drum contact B) severe heat checking C) slow release D) spring brakes not fully releasing
B
Compressors are ________ A) located in the cylinder head B) engine driven C) normally closed D) like an in-line filtration system
B
Foot valves are ________ devices. A) pressure imbalanced B) self-balancing C) pressure-compensating D) pneumatically balanced
B
How thick is a brake block ? A ) 0.055 " thick B ) 3/4 " thick C ) 0.01 " thick D ) 1/2 " thick
B
Hydraulic brake systems use vacuum boosters , which loose efficiency ________ A ) under emergency conditions B ) at high altitudes c)at shorter stopping distances D ) at high speeds
B
In ________ the bearing cup and bearing bores are machined seat - to - seat to precise tolerances in a climate - controlled factory . A ) standard hubs . B ) preset hubs C ) cast - iron spoke wheels D ) dual tires
B
Primary brake circuits are commonly color coded as what color air lines? A) Blue B) Green C) Black D) Red
B
Some movement of the brake _________ should be present on all disc brakes. A) shoe B) caliper C) air pressure D) rotor
B
The consequence of ________ is that the tires begin to skid , and the driver loses the ability to steer the vehicle . A ) inertia shift B ) wheel lock - up C ) brake fade D ) brake torque
B
The consequence of ________ is that the tires begin to skid, and the driver loses the ability to steer the vehicle. A) inertia shift B) wheel lock-up C) brake fade D) brake torque
B
The trailer control valve should never be used for ________ A) bobtailing B) parking C) towing D) braking
B
The trailer control valve should never be used for __________ A) bobtailing B) parking C) towing D) braking
B
Two color-coded flexible hoses connect the tractor and trailer air system. What color is used for the supply/emergency circuit? A) Yellow B) Red C) Green D) Blue
B
Unbalanced brake pressures can be caused by _________ A) glazed friction material B) malfunctioning relay valves C) polished drums or rotors D) improperly installed automatic slacks
B
What are used to prevent a total loss of braking if a failure occurs ? A ) Parking brakes B ) Separate circuits C ) Roto-chambers D ) Power springs
B
What are used to prevent a total loss of braking if a failure occurs? A) Parking brakes B) Separate circuits C) Roto-chambers D) Power springs
B
What controls air system pressure by stopping and starting compressor loading? A) Air dryer B) Governor C) Air reservoir D) Check valves
B
What is installed behind the seal lip to hold the seal firmly to the shaft ? A ) Spacer B ) Garter spring C ) Tire bead D ) Pilot pad
B
What system is needed to control axle movement ? A ) Air disc B ) Suspension C ) Brake foundation D ) Hydraulic actuation
B
What type of material is identified by a stencil on its edge and called an edge code? A) Semi-metallic B) Brake block friction C) Vaporized lining D) Glazed lining
B
What type of noise is typically caused by vibrating parts? A) Squeaking B) Squealing C) Hissing D) Grinding
B
What will removing the spring brake actuator require? A) Burnishing B) Caging the power spring C) Synchronization D) Minimum air pressure
B
When brakes are properly adjusted, the angle formed between the brake chamber pushrod and the arm of the slack adjuster is how many degrees? A) 30° B) 90° C) 50° D) 75°
B
Where are air intake and discharge valves located? A) Crankshaft B) Cylinder head C) Crankcase D) Intake manifold
B
Which of the following are precisely machined for consistent width between the bearings ? A ) Spindles B ) Spacers C ) Retaining nuts D ) Crush sleeves
B
Which of the following are precisely machined for consistent width between the bearings ? A ) Spindles B) Spacers C ) Retaining nuts D ) Crush sleeves
B
Which of the following easily radiates heat and does not harden with time and vibration? A) Carbon B) Annealed copper C) Cast iron D) Stainless steel
B
Which of the following is an unintended left or right direction change by a vehicle during a brake application? A) Torque balance B) Brake pull C) Brake balance D) Brake timing imbalance
B
Which of the following is produced by slow brake applications or a brake that is lightly dragging along a drum ? A ) Friction B ) Glazed linings C ) Heat fade D ) Brake torque
B
Which of the following is the distance from its hub mounting surface to the centerline of the wheel ? A ) Rim width B ) Wheel offset C ) Rim diameter D ) Wheel end
B
Which of the following is the distance from its hub mounting surface to the centerline of the wheel ? A) Rim width B ) Wheel offset C ) Rim diameter D ) Wheel end
B
Which of the following refers to the size or surface area of a brake chamber multiplied by the length of the slack adjuster in inches ? A ) Force multiplication B ) AL factor C ) Edge code D ) Brake design factor
B
Which of the following refers to the size or surface area of a brake chamber multiplied by the length of the slack adjuster in inches? A) Force multiplication B) AL factor C) Edge code D) Brake design factor
B
Worn leaking __________ for range control cylinders can leak internally inside a transmission and can be hard to pinpoint. A) governor air lines B) O-rings C) glad hand seals D) air dryer purge valves
B
________ is the measure of twisting force applied to wheel fasteners . A ) Tire pressure B ) Torque C ) Load D ) Bearing preload
B
_________ is a problem that can be described as the inability of the brakes to maintain their effectiveness . A ) Anti - fade B ) Brake fade C ) Brake torque D ) Inertia shift
B
_________ is created by having equal air pressure at all wheel ends at the same time. A) Pneumatic imbalance B) Pneumatic balance C) Torque imbalance D) Torque balance
B
_________ is the measure of twisting force applied to wheel fasteners . A ) Tire pressure B ) Torque C ) Load D ) Bearing preload
B
same time? What system design prevents both the service brakes and the parking brakes being applied at the A) Tractor protection B) Anti-compounding C) Hydraulic brake D) Automatic transmission retarder
B
A cam - same camshaft rotates in the same direction as the ________ to energize the brakes . A ) actuator chamber B ) wheel end C ) drum D ) brake shoe
C
A standard brake chamber has a ( n ) ________ stroke travel . A ) 3 " B ) 1.25 " C ) 2.5 " D ) 8 "
C
Air brake systems multiply and transfer brake pedal force using the properties of _______ A) crack pressure B) hydraulic pressure C) air pressure D) torque
C
Air brake systems multiply and transfer brake pedal force using the properties of ________ A) crack pressure B) hydraulic pressure C) air pressure D) torque
C
Air dryers use a replaceable desiccant cartridge to trap oil and water discharged from the compressor by a process known as _______ A) combustion B) pressure-protection C) adsorbtion D) consumption
C
Air dryers use a replaceable desiccant cartridge to trap oil and water discharged from the compressor by a process known as ________ A) combustion B) pressure-protection C) adsorbtion D) consumption
C
Compressor consists of three major sections: a cylinder head, crankshaft, and the ________ A) governor B) actuator C) crankcase D) piston
C
Compressor consists of three major sections: a cylinder head, crankshaft, and the ________A) governor B) actuator C) crankcase D) piston
C
Drum wear is measured using a(n) gauge. A) duplex B) dash C) inside bore D) go/no-go
C
Hubs consist of precision manufactured bearings , seals , and a ( n ) ________ A ) axle spindle B ) axle housing C ) ABS tone wheel D ) rim flange
C
Hubs consist of precision manufactured bearings , seals , and a ( n ) _________ A ) axle spindle B ) axle housing C ) ABS tone wheel D ) rim flange
C
Pneumatic imbalance is measured with what type of gauge? A) Inside bore B) Dash C) Duplex D) Pressure
C
Silicone - based fluids are ________ which means they do not attract water and will not damage paint . A ) self - energized B ) hygroscopic C ) hydrophobic D ) glazed
C
TMC RP 618 is an established procedure for obtaining which of the following ? A ) Bearing preload B ) Proper clamping force C ) Wheel bearing end play D ) Torque
C
The _________ function is to collect any remaining water and oil left in the compressed air. A) secondary reservoir B) safety relief valve C) wet tank D) primary reservoir
C
The latest types of brake lining are no longer manufactured with any _________ fibers. A) aramid B) carbon C) asbestos D) glass
C
The most common cause of wheel seal leaks is loose wheel _______ A) bolts B ) clamps C ) bearings D) nuts
C
The most common cause of wheel seal leaks is loose wheel __________ A ) bolts B ) clamps C ) bearings D ) nuts
C
The most common failure mode for most bearings is a lack of or improper _______ A ) traction torque B ) inspection C ) lubrication D ) support
C
The most common failure mode for most bearings is a lack of or improper _________ A ) traction torque B ) inspection C ) lubrication D ) support
C
The power spring is more commonly called a _________ spring . A ) return B ) single - piece C ) maxi D ) compression
C
What brake systems use a ramp - and - roller design inside a wheel cylinder to multiply force supplied by an air chamber ? A ) Dual brake B ) Disc brakes C ) Wedge brake D ) Cam brake
C
What can be used to pinpoint leaks? A) Carpenter's square B) Application of air pressure C) Soapy water D) Cardboard card placed over compressor's air outlet
C
What happens when some wheel ends or axles work harder to brake than others? A) Brake steer B) Brake pull C) Brake imbalance D) Brake balance
C
What if friction's by - product ? A ) Braking force B ) Kinetic energy C ) Heat D ) Motion
C
What if friction's by-product? A) Braking force B) Kinetic energy C) Heat D) Motion
C
What is thought of as an axial load applied to the bearing by a threaded nut ? A ) Wheel end play B ) Positive offset C ) Preload D ) Bearing end play
C
What kind of wear can be determined by inserting a go/no-go gauge into the backing plate hole? A) Brake pad B) Brake lining C) Brake shoe D) Camshaft bushing
C
What occurs when drums expand due to heat ? A ) Chemical fade . B ) Water fade C ) Mechanical fade D ) Glazing
C
What occurs when the trailer brakes have higher levels of braking force than the tractor brakes? A) Jackknifing B) Major air leak C) Trailer swing-out D) Crack pressure
C
What type of braking should be the braking technique used when downhill braking? A) Adaptive cruise B) Emergency C) Snub D) Antilock
C
Wheel ____________ are the threaded fasteners that attach the wheel to the vehicle . A ) clamps B ) bolts C ) studs D ) nuts
C
Wheel rims , tires , and hubs are major components making up part of the axle end or , what the trucking industry calls the wheel __________ A ) housing B ) end play C ) end D ) offset
C
Wheel rims , tires , and hubs are major components making up part of the axle end or , what the trucking industry calls the wheel________ A ) housing B ) end play C ) end D ) offset
C
Which of the following are often made from metal and specialized rubber - like materials ? A ) Wheel bearings B ) Bearing spacers C ) Wheel seals D ) Preset hubs
C
Which of the following is a metallic element that provides additional lubrication and corrosion protection ? A ) Aluminum B ) Steel C ) Lithium D ) Cast - iron sheols
C
Which of the following is made up of tiny silica beads that are a tough granular material capable of adsorbing water and oil into their surface? A) Dryer inlet port B) Oil separator C) Dryer desiccant D) Purge valve
C
Which of the following is not used in any friction material today ? A ) Elastomer - like compounds B ) Aramid fibers C ) Asbestos D ) Kevlar
C
Which of the following is not used in any friction material today? A) Elastomer-like compounds B) Aramid fibers C) Asbestos D) Kevlar
C
Which of the following is responsible for removing oil passed into the air supply by the compressor? A) Exhaust port B) Service chamber C) Air dryer D) Air reservoir
C
Which of the following is the source of power for the air brake system? A) Actuator B) Primary circuit C) Air compressor D) Governor
C
Which of the following maintains shoe to drum clearance established during an initial adjustment? A) Manual slack adjusters B) Brake adjustment indicators C) Automatic slack adjusters D) Free stroke measurement
C
Which of the following provides a connection point for brake drums and torque transfer to the wheels ? A ) Drive axle B ) Bearings C ) Hubs D ) Rims
C
Which of the following refers to the amount of force required to move an object while in contact with another ? A ) AL factor Toda B ) Brake block C ) Coefficient of friction D ) Brake torque
C
_______ refers to the number and spacing of the wheel the wheel rim A ) Wheel offset B ) Preload C ) Bolt pattern D ) Wheel end
C
_________ valves adjust braking force when a tractor is not pulling a trailer A) Quick-release B) Relay C) Proportioning D) Anti-compounding
C
__________ valves adjust braking force when a tractor is not pulling a trailer A) Quick-release B) Relay C) Proportioning D) Anti-compounding
C
A cause of a grinding noise when the brakes are applied would include ________ A) poor lining-to-drum contact B) glazed lining and or drums. C) foreign material embedded in friction material D) loose lining, brake block, or shoes
C.
__________ is minimal in air disc systems because rotors are squeezed rather than pushed outwards like drums . A ) Anti - fade : B ) Brake torque C ) Brake fade D ) Slack
C.
An air signal line connects the governor's unloader port to the dryer's ________ valve. A) quick-release B) foot C) relay D) purge
D
Brakes convert the vehicle's kinetic energy into heat energy using ______ A ) deceleration B ) energy of motion C ) traction control D ) friction
D
Brakes convert the vehicle's kinetic energy into heat energy using _______ A) deceleration B) energy of motion C) traction control D) friction
D
Braking odors are typically related to overheated ________ A) brake shoes B) brake drums C) bushings D) brake linings
D
Centrifuge brake drums are made with a cast iron core surrounded by a ( n ) ________ A ) vaporized lining B ) glass fiber C ) elastomer - like compound D ) steel band
D
Centrifuge brake drums are made with a cast iron core surrounded by a(n) ________ A) vaporized lining B) glass fiber C) elastomer-like compound D) steel band
D
Connections to air reservoirs for vehicle accessories are one of many possible sources of _________ A) air buildup time B) squealing and grinding noises C) glazing D) air leakage
D
Correct hub and drum combinations are required to prevent broken bolts , damage to drums , and ___________ A ) excessive end play B ) total loss of braking C ) full application of brake torque D ) loose wheels
D
During brake fade , the brakes ' stopping power is _______ A ) controlled B ) increased C ) adjusted D ) reduced
D
During brake fade, the brakes' stopping power is ________ A) controlled B) increased C) adjusted D) reduced
D
Excessive ________ can lead to brake failure. A) engine crankcase pressure B) air buildup time C) oil pumping D) clearances
D
How often should air tanks be drained? A) Weekly B) Monthly C) Yearly D) Daily
D
If the complaint for an air brake systems is that the there is a slow pressure build-up, the component involved would be which of the following? A) Air gauge B) Governor C) Safety valve D) Compressor
D
One disadvantage of air systems would be which of the following? A) Air systems use simpler foundation brakes. B) Air systems require bleeding of air each time they are opened to connect to another vehicle. C) Vacuum boosters lose effectiveness with increased altitude. D) The air must be pressurized, filtered, and stored in large, multiple reservoirs.
D
One example of a strategy to reduce energy consumption is to have the compressor load during vehicle-engine __________ A) injection B) acceleration C) combustion D) deceleration
D
Semi - liquid synthetic grease is commonly used in _________ A ) wheel seals B ) wheel studs C ) standard hubs D ) preset hubs
D
Semi - liquid synthetic grease is commonly used in __________ A ) wheel seals B ) wheel studs C ) standard hubs D ) preset hubs
D
The spokes on a cast spoke wheel support the _________ A ) wheel bearings B ) drive axle C ) axle housing D ) tire rim
D
The spokes on a cast spoke wheel support the ____________ A ) wheel bearings B ) drive axle C ) axle housing D ) tire rim
D
What are installed at the end of the S - cam to minimize any cam end play ? A ) Slack adjusters B ) Grease nipples C ) Bushings D ) Shims
D
What are installed at the end of the S-cam to minimize any cam end play? A) Slack adjusters B) Grease nipples C) Bushings D) Shims
D
What are the braking components found at the wheel ends ? A ) Roto - chambers B ) Floating calipers C ) Dual brake circuits D ) Brake foundations
D
What is used to construct the compressor? A) Steel B) Nylon C) Silica D) Cast iron
D
What is used to construct the compressor? A) Steel B) Nylon C) Silica ti D) Cast iron
D
Wheels are usually made from cast aluminum alloy or ________ A ) rubber - like materials B ) cast - iron C ) magnesium D ) steel
D
Wheels are usually made from cast aluminum alloy or _________ A ) rubber - like materials B ) cast - iron C ) magnesium D ) steel
D
Which of the following are the air couplers attached to the trailer hoses connecting the tractor and trailer air systems? A) Circuits B) Boosters C) Governors D) Gladhands
D
Which of the following controls air system pressure by stopping and starting compressor loading? A) Air intake valves B) Unloader C) Air discharge valves D) Governor
D
With standard hubs , A ) bearing end play is factory pre - set B ) there are no end pay errors C ) hub assembly is completely assembled from factory D ) individual components are assembled by a technician
D
With standard hubs , ________ A ) bearing end play is factory pre - set B ) there are no end pay errors C ) hub assembly is completely assembled from factory D ) individual components are assembled by a technician
D
Without ________ a vehicle will have a tendency to either jackknife or have the trailer swing out during hard braking events. A) reservoir protection B) air suspension C) adequate air pressure to operate the service brakes D) pneumatic balance
D
Without __________ a vehicle will have a tendency to either jackknife or have the trailer swing out during hard braking events. A) reservoir protection B) air suspension C) adequate air pressure to operate the service brakes D) pneumatic balance
D
_________ chambers are actuators with a unique diaphragm construction that delivers consistent output force regardless of the pushrod position . A ) Spring brake B ) Brake C ) Long stroke D ) Roto
D
_________ correct excess pushrod travel from increased drum to lining clearance produced by brake wear . A ) Roto chambers B ) Power springs C ) Actuators D ) Slack adjusters
D
