Deck 33: Heavy-Duty Truck Trailers

Question 1

What is the industry standard fifth-wheel height?

A) 52 inches
B) 48 inches
C) 44 inches
D) 42 inches

Answer 1

B

Question 2

Which type of trailer floor design would be most suitable for use in a refrigerated trailer?

A) duct-type floor
B) T-bar-type floor
C) hybrid T-bar duct
D) ship lapped,laminated oak

Answer 2

C

Question 3

A semi-trailer with three axles,a fifth wheel,and known as a lead trailer would be part of which of the following vehicle combinations?

A) A-Train
B) B-Train
C) C-Train
D) D-Train

Answer 3

B

Question 4

Which of the following interior compartment temperatures are commonly used for refrigerated freight?

A) 35 degrees F (2 degrees C)
B) 0 degrees F (-18 degrees C)
C) -20 degrees F (-29 degrees C)
D) all of the above

Question 5

What type of highway train combination is made up of a tractor,two semi-trailers,and one converter dolly,drawbar and pintle hook assembly?

A) A-Train
B) B-Train
C) C-Train
D) D-Train

Question 6

Which of the following is NOT an advantage of fiber reinforced plywood (FRP)panels over aluminum in trailer construction?

A) lighter weight
B) easier to replace
C) better corrosion resistance
D) lasts much longer

Question 7

Which of the following highway train combinations does not use a converter dolly?

A) A-train
B) B-Train
C) C-Train
D) D-Train

Question 8

What is the maximum height permitted on any highway truck or trailer operated in the USA,Mexico,or Canada?

A) 10 feet 8 inches (3.25 meters)
B) 12 feet 6 inches (3.81 meters)
C) 13 feet 6 inches (4.11 meters)
D) 14 feet 8 inches (4.47 meters)

Question 9

Which part of the trailer flooring suffers the most abuse and usually needs the most reinforcement and repair?

A) rear four feet
B) front four feet
C) area directly over the suspension
D) area directly over the landing gear

Question 10

What is the essential difference between an A-Train and a C-Train?

A) C-Train is longer
B) A-Train is longer
C) C-Train has a rigid double-drawbar system
D) A-Train has more pivot points

Question 11

Which of the following describes a semi-trailer?

A) any trailer that is less than 53 feet long
B) trailer that whose weight must be partially supported by another vehicle
C) any trailer used in a linehaul application
D) trailer hauled by a class 7 or class 8 tractor

Question 12

Which of the following problems weakens the frame of a trailer constructed in the monocoque style?

A) floor rotted out
B) damaged door post
C) sagging roof
D) all of the above

Question 13

What is considered to be the standard loading dock height?

A) 48 inches
B) 54 inches
C) 56 inches
D) 60 inches

Question 14

Which of the following differentiates a D-train combination from other multi-trailer highway trains?

A) articulation between the lead and pup is removed
B) articulation between the tractor and lead trailer is removed
C) three points of articulation
D) two points of articulation

Question 15

If 60 feet (18 meters)of wiring is required to safely connect a circuit that has an 8-amp operating load,what U.S.standard wiring gauge is required?

A) 18 AWG
B) 16 AWG
C) 12 AWG
D) 10 AWG

Question 16

How many articulation points are there in a complete A-train combination?

A) one
B) two
C) three
D) four

Question 17

Which of the following have lowered the electrical current load and reduced maintenance downtime on trailer wiring systems?

A) LED lighting
B) modular wiring
C) plug-in connectors
D) all of the above

Question 18

What is the longest permissible length of a semi-trailer allowed on most US,Mexican,and Canadian highways (in some jurisdictions this may be lower,some higher)?

A) 44 feet (13.4 meters)
B) 48 feet (14.6 meters)
C) 53 feet (16.2 meters)
D) 57 feet (17.4 meters)

Question 19

Which type of doors would you find on a trailer used primarily for pick-up and delivery work?

A) roll-up rear door
B) single-swinging rear door
C) double-swinging rear door
D) tail gate

Question 20

How are some trailer-specific tires different from truck tires?

A) trailer tires are lighter in weight
B) trailer tires usually have shallower treads
C) trailer tires usually last longer
D) all of the above

Question 21

Which of the following refrigerants has the lowest ozone depletion potential (ODP)rating?

A) R-134a
B) R-22
C) R-12
D) R-422D

Question 22

Which of the following values would represent typical maximum cooling capacity of a refrigerated van?

A) 12,000 Btu (12,660 kj)
B) 14,000 Btu (14,770 kj)
C) 18,000 Btu (18,991 kj)
D) 25,000 Btu (26,376 kj)

Question 23

Technician A says cryogenic reefers units have a heavy carbon footprint and ODP rating.Technician B says that R-22 has been approved for use in refrigerated trailers until the year 2020.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 24

Which of the following is the most common crossmember spread used in the sub-frame of a van semi-trailer?

A) 6-inches (150 mm)
B) 9-inches (230 mm)
C) 12-inches (300 mm)
D) 18-inches (460 mm)

Question 25

What supports the front end of a semi-trailer when it is uncoupled from a tractor and parked?

A) upper coupler
B) dolly legs
C) lift axle
D) nose plate

Question 26

What is a commonly used term meaning a hinged trailer door?

A) roll-up
B) swinger
C) tail gate
D) all of the above

Question 27

Which of the following van type trailers offers the convenience of loading from the side?

A) open-top van
B) curtain-sided
C) roll-up
D) swinger

Question 28

Technician A says that most van semi-trailers use unibody construction.Technician B says that most van semi-trailers use monocoque construction.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 29

Which of the following terms has the same meaning as landing gear on a trailer?

A) duals
B) tandem axle
C) dolly legs
D) lift axle

Question 30

Who sets the performance standards required for reefer vans used on NAFTA (U.S.A.,Canada and Mexico)highways?

A) American Trucking Association
B) Technology and Maintenance Council
C) American Refrigeration Institute
D) Society of Automotive Engineers

Question 31

What is the cooling capacity of reefer units measured in?

A) BHP (watts)
B) lb.-ft.(N.m)
C) atms (bar)
D) Btus (joules)

Question 32

What is the common screw size used to secure laminated oak floor boards to a van trailer sub-frame?

A) 1/4-inch (6 mm)
B) 5/16-inch (8 mm)
C) 3/8-inch (10 mm)
D) 7/16-inch (11 mm)

Question 33

What does the term reefer refer to in the trucking industry?

A) refrigerated van trailer
B) truck air-conditioning system
C) torque multiplier
D) wedge-shaped bar

Question 34

When a refrigerated trailer is divided into three compartments,each managed at a different temperature,which of the following is required?

A) separate reefer unit for each compartment
B) separate condenser for each compartment
C) separate evaporator for each compartment
D) separate computer for each compartment

Question 35

Which of the following is an advantage of a tongue and groove,laminated oak floor in a unibody semi-trailer?

A) tough and weather resistant
B) adds to structural integrity of frame
C) withstands forklift truck and skid abuse
D) all of the above

Question 36

To which of the following assemblies is a kingpin either welded or bolted?

A) upper coupler
B) lower coupler
C) fifth wheel
D) drawbar eye

Question 37

What does the eye on a drawbar connect to?

A) upper coupler
B) lower coupler
C) fifth wheel
D) pintle hook

Question 38

Technician A says that most of the engines used in current refrigerated trailers are gasoline fueled.Technician B says that both the engine and temperature control systems used in current refrigerated trailers are electronically managed.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 39

Which of the following best describes the function of a converter dolly?

A) converts a full trailer to a semi-trailer
B) converts a semi-trailer to a full trailer
C) allows trailer payload to be increased
D) usually couples a trailer directly to a tractor

Question 40

What is the usual maximum width of a trailer permitted on a North American highway?

A) 96-inches (2.44 meters)
B) 102-inches (2.59 meters)
C) 108-inches (2.74 meters)
D) 112-inches (2.84 meters)

Question 41

When a sliding trailer bogie is used,how many mechanical locking pins are used on a typical unit?

A) one
B) two
C) four
D) eight

Question 42

Which of the following AWG wiring sizes is the minimum that should ever be used on any trailer light circuit?

A) 12 gauge
B) 16 gauge
C) 18 gauge
D) 20 gauge

Question 43

Technician A says that power line carrier (PLC)permits multiplexing to take place between a trailer and the tractor data bus on a non-dedicated wire.Technician B says that PLC messages are RF-superimposed over the blue 12-volt auxiliary power supply between the tractor and trailer.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 44

What type of liner is required in an acid tanker?

A) stainless steel
B) non-reactive
C) non-toxic
D) mild steel

Question 45

A crack is visible in a lens used in a sealed trailer tail light assembly but the light operation is not affected.Technician A says that the crack should be sealed with some silicone RTV to ensure no moisture enters.Technician B says that the cracked lens should be replaced.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 46

What would be the maximum cubic capacity of a typical full size semi-trailer dump box?

A) 10 yards (7.65 cubic meters)
B) 15 yards (11.5 cubic meters)
C) 20 yards (15.3 cubic meters)
D) 30 yards (23 cubic meters)

Question 47

Which of the following must be true of milk tanker trailer?

A) no internal bulkheads
B) must be equipped with tank pop-off valve
C) must be equipped with tank rupture disk
D) no upper hatch flange

Question 48

What on-trailer device is used to track trailer mileage for purposes of maintenance scheduling?

A) odometer
B) tractor data bus
C) hubdometer
D) trailer data bus

Question 49

What is most commonly used to pressurize a dry bulk pressure hopper to blow off loads?

A) truck PTO pump
B) trailer PTO pump
C) truck PTO compressor
D) trailer PTO compressor

Question 50

When a semi-trailer bogie is moved either forward or rearward,what is changed?

A) length of trailer
B) trailer bridge formula
C) tractor bridge formula
D) all of the above

Question 51

Technician A says that the red and white reflective tape required by the NHTSA on trailers should be adhered as close to 6 feet (1.8 meter)above road level as possible.Technician B says that this reflective tape is known as conspicuity tape.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 52

Which of the following has greatly reduced trailer lighting circuit problems?

A) silicone RTV
B) black electrical insulating tape
C) shrink wrap
D) LED light units

Question 53

What legislation governs trailer lighting standards in the United States?

A) FMVSS-101
B) FMVSS-108
C) FMVSS-121
D) FMVSS-180

Question 54

If a bogie is moved forward on a semi-trailer,which of the following will be true?

A) percentage of trailer load supported by tractor rear suspension increases
B) percentage of trailer load supported by trailer suspension decreases
C) percentage of trailer load supported by trailer suspension increases
D) percentage of trailer load supported by tractor front suspension increases

Question 55

Technician A says that the most common cause of trailer landing gear failures is crank gear tooth failure.Technician B says that landing gear is designed to sustain vertical weight forces and not the effects of the horizontal ramming that takes place during coupling.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 56

Which of the following media is used in a cryogenic refrigerated unit?

A) R-422D
B) R-22
C) liquid nitrogen
D) liquid oxygen

Question 57

Which of the following trailer types is required to haul liquid asphalt?

A) drop belly dump
B) dry bulk,pressure hopper
C) hot material,tanker
D) refrigerated tanker

Question 58

How should trailer hand-crank landing gear legs and crankcase be lubricated?

A) multi-purpose gear lube
B) SAE 30W engine oil
C) grease applied through zerks
D) penetrating oil

Question 59

Technician A says that 16.5-inch by 7-inch brakes are the most common size found on trailer S-cam actuated brakes.Technician B says that many trailer manufacturers are adopting wedge brakes due to their lower maintenance costs.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 60

Which of the following trailers should be used to haul dry cement?

A) open top belly dump
B) mixer barrel trailer
C) slant front bathtub dump
D) dry bulk pressure hopper

Question 61

Which trailer valve receives air from the trailer air tanks and routes it to the service brake chambers to apply and release the service brakes?

A) two-way check valve
B) service relay valve
C) spring brake control valve
D) pressure protection valve

Question 62

If a trailer is equipped with a service brake priority air system and all its reservoirs are empty,which of the following must occur before the trailer brakes can be released?

A) all service chambers must be charged
B) air tanks must be charged to 60 psi before the hold-off circuit is charged
C) the service signal circuit must be activated
D) spring brakes over one axle must be caged

Question 63

What is the reason for modulating hold-off pressure in the spring brake circuit?

A) faster park/emergency brake application
B) modulated park/emergency brake application
C) more aggressive service braking
D) modulated service braking

Question 64

When setting a rivet using a pneumatic rivet gun,what tool should be used on the shank side of the rivet gun to form the bucked head?

A) ball peen hammer
B) rivet set
C) cold chisel
D) bucking bar

Question 65

What is the FMVSS-121 minimum required stopping distance for a tractor-trailer semi rig built after 2010?

A) 125 feet
B) 250 feet
C) 350 feet
D) 500 feet

Question 66

What is used as the control signal for the spring brake relay valve on a trailer?

A) blue knob on dash
B) yellow knob on dash
C) red knob on dash
D) trailer hand control valve

Question 67

When system air pressure is routed into the trailer hold-off circuit,the parking brakes are:

A) 50% applied
B) 100% applied
C) 50% released
D) fully released

Question 68

Technician A says that the bucked side of a rivet is usually countersunk.Technician B says that any bucked head should be formed with an even radius.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 69

What is the function of a trailer pressure protection valve?

A) maintain reservoir pressure
B) maintain pressure in the service line
C) maintain pressure in the supply line
D) maintain pressure in the brake chamber

Question 70

Which of the following would be more likely to result in flat spots on trailer tires?

A) unbalanced braking
B) wheel hop
C) uneven trailer loading
D) suspension lean

Question 71

What activates the signal used to actuate trailer service braking?

A) dash valve
B) trailer hand valve
C) foot valve
D) either b or c

Question 72

A trailer with two air tanks suffers a total loss of pressure in one reservoir.Which of the following should prevent immediate dynamiting of the trailer brakes?

A) service brake relay valve
B) spring brake control valve
C) pressure protection valve
D) hold-off quick release valve