heavy duty truck systems final Part A

92. A technician greasing a driveshaft slip spline assembly applies lubricant until it appears at the pressure relief hole. What should be done next? a. cover the relief hole with a finger and add some more lubricant b. cease applying lube to avoid over-greasing c. continue applying lube until it appears at the slip yoke seal d. both A and C

d. both A and C

94. Which ofthe following types of universal joint damage would most likely result from improper installation? a. galling b. spalling c. pitting d. brinelling

d. brinelling

79. What is an auxiliary drive system for chassis accessories such as hydraulic pumps driven by the transmission known as? a. auxiliary transmission b. drop box c. transfer case d. power-takeoff (PTO)

d. power-takeoff (PTO)

95. Which ofthe following methods of separating a U-joint from a driveshaft yoke when it is on the truck, is preferred? a. hydraulic jack on yoke hub b. 50 1b slide hammer on yoke c. 16 1b sledge hammer d. two-jaw U-joint puller

d. two-jaw U-joint puller

90. Which of the following describes a broken back driveline arrangement. a. working angles of its U-joints are equal b. companion flanges or yokes are not parallel c. both A and B d. neither A nor B

c. both A and B

76. A gear of 12 inches in diameter is driving a second of 24 inches in diameter. Which of the following will result from the driven gear? a. speed increase only b. torque reduction, increased speed c. increased torque, reduced speed d. torque increase only

c. increased torque, reduced speed

83. When a yoke seal race is damaged, which of the following is the cost-effective repair method? a. polish race with a crocus cloth b. machine the race to an undersize c. resleeve with a wear ring d. replace the yoke

c. resleeve with a wear ring

98. If you add shims to a longitudinal torque rod attached to the forward drive axle carrier in a tandem drive truck, which of the following will result? a. only the working angles of the U-joints in the front driveshaft will change b. only the working angles of the U-joints in the rear driveshaft will change c. the working angles of the U-joints in both driveshafts will change d. no U-joint working angles will be affected

c. the working angles of the U-joints in both driveshafts will change

74. How many countershafts are used in the forward section of a RoadRanger transmission? a. none b. one c. two d. three

c. two

84. Which of the following methods of heating a transmission bearing should be used to ensure that no bearing damage occurs ? a. use an oxy-acetylene cutting torch b. use a rosebud c. use a bearing hotplate and Tempilstick

c. use a bearing hotplate and Tempilstick

14. Which of these terms mean the same thing as Voltage? A. Charge differential B. Electromotive force C. Potential difference D. All of the above

d. All of the above

91. Which of the following would represent ideal operating conditions for a pair of universal joints on a propeller shaft? a. maximum operating angle of 3 degrees b. minimum operating angle of 1/2 degree c. operating angles each U-joint should be within 1 degree d. all of the above

d. all of the above

96. When attempting to dynamically balance a truck driveline, which of the following must be done? a. all the wheels must be off the ground b. the frame must be level c. the transmission and differential carrier must be at the same angle raised as on the ground d. all of the above

d. all of the above

75. When discussing the rotation of gears and shafts in a truck transmission, which of the following terms can be used to describe clockwise rotation? a. forward b. right-hand c. left-hand d. both A and B e. both A and C

d. both A and B

22. When a diode allows current to flow through it, what state is it in?A. forward bias B. reverse bias C. neutral bias D. none of the above

A. forward bias

24. With which part of a computer processing cycle are sensors associated with? A. input B. processing C. output D. actuator

A. input

41. What is the function of a tachometer? A. measures engine rpm B. measures road speed C. displays engine hours D. displays exhaust gas temperature

A. measures engine rpm

43. Which American Trucking Association, Technical and Maintenance Council (TMC) recommended practice (RP) outlines the placement of instrument cluster gauges? A. RP 401 B. RP 285 C. RP 121 D. RP 108

A. RP 401

1. What is the maximum allowable stroke for a type 30, clamp type brake chamber? A. 2" B. 1 3/4" C. 2 1/2" D. 8 3/32"

A. 2"

34. When does an energized diesel engine cranking motor produce peak torque? A. At close to stall RPM B. At the equivalent of 225 engine rpm C. At maximum cranking motor rpm D. After 15-seconds of cranking

A. At close to stall RPM

13. Vehicle wiring schematics use which theory of current flow almost exclusively? A. Conventional theory B. Electron theory C. Gilbert theory D. Faraday theory

A. Conventional theory

7. What happens when Ethylene-glycol (EG) is mixed with water at a ratio exceeding 68:32? A. Freeze point increases B. Freeze point decreases C. Freeze point does not change D. It changes to gel

A. Freeze point increases

25. When preparing to load test a lead-acid battery, the technician first checks the integral hydrometer and sees that it is dark. What should be done next? A. Fully charge the battery before attempting to test it B. Replace the battery, it has a low electrolyte level C. Proceed with the test, the battery is fully charged D. Remove the surface charge, then proceed to test the battery

A. Fully charge the battery before attempting to test it

68. As clutch friction facings wear on a truck pull-type clutch, how is clutch pedal free travel affected? A. decreases B. increases C. unaffected

A. decreases

10. If you see evidence of welding on a trailer pintle hook while inspecting a trailer, what should you do? A. OOS deadline the vehicle B. Grind the weld profile smooth C. Test the pintle hook with a hammer D. Despatch the vehicle

A. OOS deadline the vehicle

36. Technician A says that the best way of locating high resistances in a cranking circuit is by using voltage drop testing. Technician B says that using an ohmmeter can locate high resistance stater cable. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

A. Technician A only

42. Technician A says that HID headlamps convert about 80% of the electrical energy they consume into light energy. Technician B says that halogen lights use more energy but produce a 20% brighter beam than equivalent HID beams. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

A. Technician A only

56. Technician A says that a reading of one psi on a pressure gauge is equal to approximately 2-inches of Hg (mercury) measured on a manometer. Technician B says that one inch of Hg is equivalent to approximately 2-inches of H20 on a manometer. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

A. Technician A only

65. Technician A says that ISO 32 is the most commonly used viscosity grade for hydraulic fluids. Technician B says that ISO 32 is equivalent to SAE 20 grade. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

A. Technician A only

51. What is the primary advantage of the SAE J-1939 data bus that is used on truck chassis? A. system can be read by generic software B.system can be programmed with generic software C. audit trails can be read with generic software D. system can be interactively diagnosed using generic software

A. system can be read by generic software

46. When soldering copper wire in medium gauge truck electrical circuits, what should be used to produce the heat? A. use cold melt solder only B. 100 watt soldering gun C. 500 watt soldering iron D. propane torch

B. 100 watt soldering gun

18. How many volts are required to push 3 amps through a resistance of 4 ohms? A. I volt B. 12 volts C. 7 volts D. 1 1/4 volts

B. 12 volts

55. If you had a pressure gauge calibrated in psia that was subject only to atmospheric pressure, what would be displayed on its scale at sea level? A. zero B. 14.7 C. 29.8 D. 101.3

B. 14.7

30. When load testing a fully charged, lead-acid battery at 80 degrees Fahrenheit at one half the rated CCA for 15 seconds, what is the lowest acceptable voltage during the test? A. 8.5 volts B. 9.6 volts C. 10.2 volts D. 12.6 volts

B. 9.6 volts

5. Which of the following gear lube classifications would be appropriate for use in the most current truck differential carriers? A. API GL-4 B. API GL-5 C. API GL-6 D. API GL-7

B. API GL-5

53. Who's law states that when pressure is applied to a confined liquid, the force is applied to the area of containment will be uniform throughout? A. Bernoulli B. Pascal C. Charles D. Boyle

B. Pascal

11. Which theory of electrical current flow states that current flows from a negative location to a positive location in an electrical circuit? A. Kilowatt law B. Electron theory C. Conventional theory D. Ohm's law

B. Electron theory

45. The technology that superimposes dash display data onto the windshield within the driver's line of sight is known as: A. DVD B HUD C. HID D. LED

B. HUD

15. Which of the following devices does NOT rely upon the principles of electromagnetism to function? A.Solenoid B. Headlight. C.Relay D.Ignition coil

B. Headlight.

16. Which of the following circuits has only one path for current to flow? A. Parallel B. Series C. Series-parallel D. None of the above

B. Series

44. Technician A says that HID headlamps frequently fail because they are more vulnerable to road shock and vibration than halogen filament lamps. Technician B says that when HID headlamps fail, it is usually due to frequent cycling. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

B. Technician B only

61. Technician A says that a vane pump is classified as non-positive. Technician B says that a gear pump uses a positive displacement pumping principle. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

B. Technician B only

69. Technician A says that one of advantages of a clutch brake is its ability to bring a vehicle to a halt at LOW speeds. Technician B says that improper use of a clutch brake when bring a vehicle to a halt can destroy it. Who is correct? A.Technician A only B. Technician B only C. Both A and B D. Neither A nor B

B. Technician B only

39. When using a carbon pile to load test a battery, which of the following occurs as you turn the control knob clockwise? A. resistance reading increases B.current reading increase C. voltage reading increases D. voltage and current readings increase

B. current reading increase

57. Which of the following expresses flow rate in a hydraulic circuit? A. feet per second (fps) B. gallons per minute (gpm) C. feet head D. all of the above

B. gallons per minute (gpm)

37. Which of the following is a disadvantage of a 42 MT starter motor? A. produces low torque B. heavy C. will not crank high compression engines D. all of the above

B. heavy

67. Which of the following could cause clutch hang-up? A. insufficient free travel B. misaligned intermediate plate drive pins C. seized throw-out bearing D. stretched clutch linkage rod

B. misaligned intermediate plate drive pins

58. In a confined hydraulic circuit, what must happen when there is flow through the circuit? A. pressure rise B. pressure drop C. fluid leakage D. fluid pressure spikes

B. pressure drop

27. The term used to describe the weight of a volume of a liquid versus the weight of an equal volume of pure water is: A. atomic mass B. specific gravity C. relative gravity D. liquid mass

B. specific gravity

70. Which of the following components can easily be modified for use as a pilot shaft for installing clutch assemblies? A. clutch fork shaft B. transmission input shaft C. axle stub D. transmission tailshaft

B. transmission input shaft

23. How many terminals are there on a diode? A. one B. two C. three D. four

B. two

71. When installing a clutch pack assembly, at what point should you knock out the wood chocks that hold Off pressure plate spring pressure? A. before mounting clutch to the flywheel B. when pressure plate is bolted tight to the flywheel C. after installing the transmission D. final step before starting the engine

B. when pressure plate is bolted tight to the flywheel

33. If you do not apply an electrical load to the batteries when full-fielding an alternator, which of the following could result? A. high voltage spikes B. damage to electrical componentS C. damage to electronic components D. all of the above

D. all of the above

12. What type of signal is produced by an Inductive pulse generator? A. Saw-tooth B. Square-wave C. AC Sine Wave D. Rippled DC

C. AC Sine Wave

28. Technician A says that battery cells that require frequent topping up is an indication of over-charging. Technician B says that voltage regulators should not be set above 14.1 volts on many current trucks. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

C. Both A and B

59. Technician A says that accumulators are used to store potential energy in a hydraulic circuit. Technician B says that accumulators are used to dampen shock and buffer sudden pressure rises. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

C. Both A and B

62. Technician A says that changing the swash angle in a swash plate pump varies the displacement of the pump. Technician B says that some swashplate pumps are fixed displacement. Who is correct? A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B

C. Both A and B

9. Which of the following lubricants is recommended for cab door hinges? A. Chassis grease B. Engine oil C. Dry graphite D. Penetrating oil

C. Dry graphite

6. Which type of antifreeze mixture should never be diluted with water? A. Ethylene-glycol B. Propylene-glycol C. Extended Life Coolant D. It is acceptable to dilute any antifreeze with water

C. Extended Life Coolant

35. Which of the following cranking circuit faults could cause slow cranking? A. weak batteries B. high viscosity engine oil C. corroded starter relay connections D. all of the above

D. all of the above

3. Which of the following trailer chassis systems usually represents the highest maintenance costs? A. Doors B. Suspensions C. Tires D. Brakes

C. Tires

66. What is the usual cause of a hydraulic oil that has a milky appearance? A. aeration B. contamination with engine oil C. contamination with water D. chemical breakdown

C. contamination with water

48. When using a DMM to measure voltage, what would happen if you placed the negative terminal on the more positive section of a circuit? A. DMM fuse would blow B. circuit would dead short through the DMM C. display reading would be preceded by a MINUS symbol D. DMM motherboard would fry

C. display reading would be preceded by a MINUS symbol

38. When the cranking circuit is energized in sub-zero conditions, the engine turns over slowly and unevenly. Which of the following would be the most likely cause? A. defective starter relay B defective starter solenoid C. gelled engine oil D. stripped flywheel ring gear

C. gelled engine oil

50. On a standard desktop PC, which of the following would be known as an input device? A. printer B. monitor C. mouse D. speaker

C. mouse

72. Which of the following clutch pack components has to always rotate at the same speed as the engine flywheel? A. pilot bearing inner race B. release bearing C. pressure plate D. friction discs

C. pressure plate

63. What type of valve is used as the primary directional control valve in most hydraulic circuits? A. ball and poppet B. gate valve C. spool valve D. pressure relief valve

C. spool valve

52. What must be used to disassemble most weatherproof connector terminals from the connector block? A. small electrical screwdriver B. sharp pointed spike C. tang release tool D. quick snap of the wrist

C. tang release tool

26. What electrolyte is used in a vehicle lead-acid battery? A. distilled water B. pure sulfuric acid C. water and sulfuric acid solution D. water and hydrochloric acid solution

C. water and sulfuric acid solution

8. When you test antifreeze with litmus paper, what are you measuring? A. Freeze point B. Nitrate protection level C. Contamination D. Acidity

D. Acidity

60. What can be used to apply force to an accumulator in a hydraulic circuit? A. spring force B. weight force C. gas pressure D. all of the above

D. all of the above

21. Which of the following best describes how a diode functions in an electrical circuit? A. current amplifier B. voltage amplifier C. relay switch D. one-way switch

D. one-way switch

81. When assembling a ten-speed, twin-countershaft transmission which of the following must be timed? a. front section b. auxiliary section c. both A and B d. neither A nor B

c. both A and B

20. Calculate the electrical pressure required to flow 6 amps through a 2 ohm resistance A.. 3 volts B. .33 volts C. 6 volts D. 12 volts

D. 12 volts

54. If you had a tubular column of one square inch diameter that extended from sea level to 50 miles into the stratosphere, how much would the air in the tube weigh? A. 101.3 kilograms B 14.7 kilograms C. 101.3 pounds D. 14.7 pounds

D. 14.7 pounds

47. What type of data connector is required to access a SAE J. 1939 bus? a. Weatherproof b. Weatherpac c. 6-pin Deutsch D. 9-pin Deutsch

D. 9-pin Deutsch

17. Which type of circuit has multiple paths for current flow? A. Series B. Series-parallel C. Parallel D. Both B and C

D. Both B and C

4. On which of the following maintenance documents does the driver have input to? A. Schedule A report B. Schedule B report C. Technician inspection report D. Driver inspection report

D. Driver inspection report

64. Which of the following types of hydraulic hose should be used to sustain the highest pressures and surge spikes? A. fabric braid B. single wire braid C. multiple wire braid D. spiral wire braid

D. spiral wire braid

40. What does the brown color code represent in a SAE/ATA standard 7-wire trailer connector cord? A. auxiliary B. brakes C. ground D. tail lights

D. tail lights

49. If you have accessed an OEM data hub, which of the following MUST be true? A. you are connected to the truck data bus B. you are working within one data bus MID C. you are viewing FMIs D. you are on-line

D. you are on-line

2. While greasing a U-Joint cross, grease exits from only 3 of the four trunnion seals. what should you do first? A. Leave it, grease will circulate in the cross. B. Replace the U-joint assembly. C. Pound on the bearing cap with a large hammer. D. Loosen the journal cap over the affected trunnion and try again.

D. Loosen the journal cap over the affected trunnion and try again.

19. A commonly used sensor that induces an AC voltage by having a rotating reluctor cut through a permanent magnetic field is used for: A. wheel speed sensors B. transmission tailshaft speed sensors C. engine speed sensors D. all of the above

D. all of the above

29. Which of the following would be a consequence of reversing the polarity of a battery bank on truck electrical system? A. battery explosion B. damage to the truck electronics C. damage to the alternator D. all of the above

D. all of the above

31. Which of the following conditions will shorten the life of batteries? A. overcharging B. undercharging C. deep-cycling D. all of the above

D. all of the above

32. Which of the following defects could result in an undercharged battery? A. loose belt(s) B. defective diode trio C. residual magnetism in the rotor D. all of the above

D. all of the above

88. Technician A says that when the WT digital display (DD) is blank, the reason could be a problem in the electrical circuit to the shift selector. Technician B says that when the WT DD is blank, the data link may have failed. Who is correct? a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

c. Both A and B

80. What is the most likely cause of a failed transmission bearing with noticeable discoloration? a. low oil level b. fretting c. fatigue d. dirt

a. low oil level

77. A gear with teeth machined straight and parallel to the shaft on which they are mounted are known as. a. spur gear b. helical gears c. amboid gears d. spiral gears

a. spur gear

78. Technician A says that when making a 5-6 upshift on a I O-speed transmission, the gearshift lever should be moved into the sixth gear position before flipping the range control button into high range. Technician B says that when making a 6-5 downshift on a 10-speed transmission, the range control button should be flipped into low range before the gearshift lever is moved into the fifth gear position. Who is correct? a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

b. Technician B only

82. Technician A says that a mechanical road speed drive cable uses a dedicated gear on the input shaft of a standard transmission. Technician B says that an inductive type road speed sensor picks up its signal from the tailshaft of the transmission. Who is correct? a. Technician A only b. Technician B only c. Both A and B d. Neither A nor B

b. Technician B only

89. Which of the following is a function of the slip yoke used on a driveshaft? a. slips to dampen clutch engagement and road shock b. allows the driveshaft to change length as differentials respond to the road profile c. permits the transmission slide back for service d. all of the above

b. allows the driveshaft to change length as differentials respond to the road profile

99. What instrument should be used to measure driveshaft runout? a. inclinometer b. dial indicator c. outside micrometer d. bore gauge

b. dial indicator

87. What is used to stop the countershafts for a shift in an AutoShift.transmission if the clutch is either defective or out Of adjustment? a. nothing, gear clash will result b. inertia brake c. clutch brake d. snubber valve

b. inertia brake

97. Which ofthe following methods can be used to adjust drive carrier operating angle when correcting driveline angles on a truck with a leaf spring rear suspension? a. cold bend axle housing b. install axle shim wedges c. rotate axle stubbs d. shim the U-joint

b. install axle shim wedges

85. What is used to signal rail position in an AutoShift transmission? a. Hall-effect sensors b. potentiometers c. variable capacitance sensors d. inductive pulse generators

b. potentiometers

93. How onen should a typical driveshaft hanger bearing be lubricated? a. when u-joints are lubed. b. they are factory lubricated and are not serviceable c. each time the slip yoke is lubed d. both A and C

b. they are factory lubricated and are not serviceable

73. When a gear with 14 teeth drives a gear with 21 teeth, how will speed and torque output be changed? a. speed increases, torque decreases b. torque increases, speed decreases c. both torque and speed decrease d. both speed and torque increase

b. torque increases, speed decreases

100. When measuring the total indicated runout (TIR) of a driveshaft, you record 0.003" positive and 0.005" negative through one shaft revolution. What is the TIR? a. 0.015 inch b. minus 0.002 inch c. 0.008 inch d. 0.002 inch

c. 0.008 inch

86. How many wiring harnesses are used to interface an AutoShift transmission to the vehicle? a. 1 b. 2 c. 3 d. 4

c. 3