2. OBJECTIVES After studying Chapter 7, the reader should be able to:
Explain how an automatic transmission hydraulic system operates.
List the valves used in an automatic transmission.
Describe the operation of the valves in an automatic transmission.
Describe how vehicle speed and load affect automatic shifts.
Follow an upshift or downshift sequence through a hydraulic schematic.

3. INTRODUCTION
The hydraulic system enables an automatic transmission to operate automatically.
The basic function of the hydraulic control system is to:
Schedule shifts to optimize engine performance,
Provide the best gear ratio for the driving conditions,
Safely shift into reverse when requested
Provide driver control of the operating ranges,
Provide engine braking to help control vehicle speed on downgrades,
Lock or unlock the torque converter clutch.

4. INTRODUCTION
FIGURE 7-1 This electronic transmission valve body (a) has only five valves. Four solenoids in the solenoid assembly (b) control shifts and torque converter clutch (TCC) apply and release. (Courtesy of Chrysler Corporation)

5. INTRODUCTION
FIGURE 7-1 (CONTINUED) This electronic transmission valve body (a) has only five valves. Four solenoids in the solenoid assembly (b) control shifts and torque converter clutch (TCC) apply and release. (Courtesy of Chrysler Corporation)

6. INTRODUCTION
FIGURE 7-2 The valve body is mounted to the bottom of the main case of transmissions and some transaxles (a). It is also mounted at the end or top of some transaxles (b). (Reprinted with permission of General Motors)

7. INTRODUCTION
FIGURE 7-3 The switch valve (a) will shift the fluid flow from circuit 1 to circuit 2 when the controlling pressure increases. This regulator valve has two servo valves (TV boost, and D2 and rev. boost) (b), which cause a pressure increase when the throttle is opened or when the transmission is shifted into D2 or reverse. This regulator valve (c) controls supply pressure to become mainline pressure.

8. INTRODUCTION
TABLE 7-1 Hydraulic System Subcircuits

9. PRESSURE DEVELOPMENT AND CONTROL
As soon as the engine starts, the torque converter hub drives the transmission pump to produce fluid flow.
Pressure is created by resistance to fluid flow.
This pressure is called:
Line
Mainline
Supply
Control pressure

10. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-4 Many pressure regulator valves have three positions. (a) The spring has moved the valve to the bottom of the bore. (b) Line pressure is moving the valve upward, opening the passage to the torque converter (circle). (c) Increased line pressure has moved the valve upward to where it can release pressure to the pump inlet (circle). Note that boost pressure in either of the two upper ports can cause a pressure increase.

11. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-5 The pressure regulator of this variable displacement vane pump can send fluid pressure to the DECREASE passage. This pressure will move the pump slide to the right and reduce pump output. (Reprinted with permission of General Motors)

12. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-6 This manual valve is arranged so it dumps line pressure to the sump in park (circle). This reduces line pressure to below 30 psi. (Courtesy of Chrysler Corporation)

13. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-7 Some pressure regulators use an adjusting screw that allows adjustment of line pressure. Others use a shim/spacer to allow an adjustment.

14. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-8 Hydraulic pressure moves this regulator valve to the left against spring tension. Pressure in the manual valve circuit will work against hydraulic pressure to increase/boost line pressure. Pressure in the overdrive clutch circuit will reduce/cut back line pressure. (Courtesy of Chrysler Corporation)

15. PRESSURE DEVELOPMENT AND CONTROL
FIGURE 7-9 Fluid from the manual valve reverse circuit acts on the primary regulator valve to increase line pressure in reverse. (Courtesy of Toyota Motor Sales USA, Inc.)

16. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
As soon as the supply circuit begins to develop pressure, the regulator valve moves slightly and opens a passage to the torque converter.
This fluid flow serves several purposes:
It ensures that the torque converter is filled so it can transmit torque from the engine to the transmission’s input shaft.
It helps control converter fluid temperature.
It provides lubrication for the moving parts inside the transmission

17. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-10 The converter and cooler feed circuit begins at the pressure regulator, goes through the converter and cooler, and then into the lube passages. Note that the cooler and the lines connecting it to the transmission are outside of the transmission. (Courtesy of Chrysler Corporation)

18. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
Torque Converter Pressure Control
Torque Converter Clutch Control
Cooler Flow
Lubrication Flow

19. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-11 When the engine is not running, the regulator valve spring moves the T/C control valve to the right, blocking the cooler passage and reducing the chance of converter drain down. Note the bypass valve that will open if the cooler becomes plugged. (Courtesy of Chrysler Corporation)

20. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-12 With the torque converter clutch (TCC) released, fluid enters this converter through the input shaft. It leaves through the area between the input shaft and the stator support. (Courtesy of Chrysler Corporation)

21. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-13 This TCC is controlled by a valve that is controlled by a solenoid that is controlled by the power train control module (PCM). When the solenoid is energized (right), the valve moves to the left, and this applies the TCC.

22. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-14 The lock-up valve and fail-safe valve control the switch valve. This in turn controls fluid flow through the converter and therefore converter lock-up. (Courtesy of Chrysler Corporation)

23. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-15 The transmission cooler is normally mounted in the colder, outlet tank of the radiator. Steel lines are normally used to connect the transmission to the cooler. (Courtesy of Chrysler Corporation)

24. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-16 This cooler has a large, flat passage from its inlet to its outlet (a). The screenlike turbulator is shown (b).

25. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-17 Cold fluid tends to stick to the walls of a plain tube cooler (top). The turbulator causes fluid turbulence to promote mixing so all of the fluid cools (bottom).

26. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-18 An auxiliary filter can be installed in one of the cooler lines to help trap contaminants (a). The cutaway view shows the internal magnet and folded paper filter element (b). (Courtesy of SPX Filtran)

27. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-19 An auxiliary cooler is mounted so the fluid flows through it and then through the standard cooler in the radiator. (Courtesy of Chrysler Corporation)

28. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-20 Transmission lube passages. Note how the passage leads to gears and bushings. (Courtesy of Toyota Motor Sales USA, Inc.)

29. TORQUE CONVERTER, OIL COOLER, AND LUBRICATION CIRCUIT
FIGURE 7-21 This planet carrier burned out from lack of lubrication; note the excess clearance and dark coloration at the planet gear shafts.

30. THROTTLE PRESSURE
A circuit carrying a throttle pressure signal is always available while the engine is running in most transmissions.
Throttle valves are pressure-regulating valves, and they provide a pressure signal that is proportionate to the load on the engine

31. THROTTLE PRESSURE
FIGURE 7-22 The throttle valve produces a pressure signal that is directly related to throttle opening or engine load. This pressure signal is used to control line pressure so that line pressure increases as the throttle is opened.

32. THROTTLE PRESSURE
FIGURE 7-23 In this hydraulically controlled transmission, the shift valves are positioned by a spring and hydraulic pressures from the throttle valve and governor. (Courtesy of Chrysler Corporation)

33. THROTTLE PRESSURE
The transmission control system uses throttle pressure to reprogram or reschedule several areas of operation:
Shift quality
Shift timing
Shift feel
Torque converter clutch control
FIGURE 7-24 Application speed of this front band is controlled by the accumulator stroke rate, and this is controlled by the shuttle valve and the 1–2 shift control valve. (Courtesy of Chrysler Corporation)

34. THROTTLE PRESSURE
FIGURE 7-25 This mechanical throttle valve is operated by a cable that is connected to the engine throttle body and accelerator pedal. (Courtesy of Chrysler Corporation)

35. THROTTLE PRESSURE Mechanical Throttle Valves Vacuum Throttle Valves
Wide-Open Throttle Kickdown Valve
FIGURE 7-26 At wide-open throttle, the kickdown valve pushes the throttle valve to the end of the bore. At this position, TV pressure is equal to line pressure in both the TV and kickdown passages. (Courtesy of Chrysler Corporation)

36. THROTTLE PRESSURE
FIGURE 7-27 With high manifold vacuum, the modulator diaphragm and modulator valve are to the left, and modulator pressure is low. When manifold vacuum drops, the spring moves the diaphragm toward the right, and modulator pressure will increase. Note the bellows used in this modulator. (Reprinted with permission of General Motors)

37. THROTTLE PRESSURE
FIGURE 7-28 Vacuum modulators have different diameters, which change the relative strength of the modulator.

38. THROTTLE PRESSURE
FIGURE 7-29 Manifold vacuum varies with load. Cruising at light load produces about 15 to 20 in. Hg. A high load produces zero vacuum,0 in. Hg. (Courtesy of Nissan North America, Inc.)

39. MANUAL VALUE
The manual valve controls the fluid flow to the band servos, clutch apply pistons, and the shift valves for the various forward and reverse gears.
This valve is also called a selector valve.
FIGURE 7-30 The manual valve is moved by the shift lever and held in position by the detent lever (cam).

40. MANUAL VALUE
FIGURE 7-31 The manual valve is in drive and the transmission is in first gear. Fluid is being sent to the rear clutch, accumulator, 1–2 shift valve, throttle valve, and governor. (Courtesy of Chrysler Corporation)

41. GOVERNOR VALVE
The transmission will begin transferring power and rotating the output shaft when the selector lever is moved to drive, intermediate, or low.
When the output shaft starts turning, the governor spins with it.
The governor is either shaft mounted (attached directly onto the output shaft) or case mounted (driven by a gear on the output shaft).

42. GOVERNOR VALVE
FIGURE 7-32 A case-mounted governor is driven by a gear on the output shaft. It provides a pressure signal relative to vehicle speed. (Reprinted with permission of General Motors)

43. GOVERNOR VALVE
FIGURE 7-33 The ideal governor pressure signal increases in exact proportion to vehicle speed, but a simple governor produces a signal that is too low at intermediate speeds or too high at higher speeds. The pressure signal from a two-stage governor comes closer to matching vehicle speed.

44. GOVERNOR VALVE
Governor valve assemblies are manufactured in four basic styles.
Two are shaft mounted, and two are case mounted:
Shaft mounted with the weight(s) opposing the valve
Shaft mounted with a primary and secondary valve
Case mounted with a pair of primary and secondary weights
Case-mounted bleed-off system

45. GOVERNOR VALVE
FIGURE 7-34 As the vehicle speeds up, centrifugal force acting on the governor weight tries to move the weight and valve toward the right to increase governor pressure. This is opposed by governor pressure at the valve, which tries to move the valve toward the left and reduce governor pressure. (Courtesy of Chrysler Corporation)

46. GOVERNOR VALVE
FIGURE 7-35 This two-stage, shaft-mounted governor uses both a primary and secondary valve. (Courtesy of Chrysler Corporation)

47. GOVERNOR VALVE
FIGURE 7-36 Centrifugal force will cause the two weights to move outward. This pushes the two balls against their seats, reducing the amount of exhaust and increasing governor pressure. (Reprinted with permission of General Motors)

48. GOVERNOR VALVE
FIGURE 7-37 Centrifugal force produces an upward force on the valve that will increase governor pressure if the valve moves. Governor pressure at the top of the valve opposes this action. The governor valve is positioned between these two forces. (Reprinted with permission of General Motors)

49. SHIFT VALVES
An upshift or downshift occurs when the shift valves move.
Shift valves are balanced between the governor pressure trying to move the valve to cause an upshift and the spring plus throttle pressure trying to resist an upshift.

50. SHIFT VALVES
FIGURE 7-38 Governor pressure can move this 1–2 shift valve from the downshift position (left) to the upshift position.

51. SHIFT VALVES
FIGURE 7-39 The 1–2 shift valve has moved to upshift, allowing drive oil to flow into the second-gear passages. Fluid pressure moves the front servo to apply the band and also strokes the accumulator piston. (Courtesy of Chrysler Corporation)

52. SHIFT VALVES
FIGURE 7-40 The 2–3 shift valve has moved to upshift. Fluid pressure will apply the front clutch and also move the front servo to release the band. (Courtesy of Chrysler Corporation)

53. SHIFT VALVES
FIGURE 7-41 Both parallel-feed shift valves are connected to drive oil (top); an upshift will occur when governor oil moves either one to the right. With series-feed shift valves, drive oil feeds only the 1–2 shift valve, and the 2–3 shift valve is fed from the 1–2 valve (bottom).

54. SHIFT VALVES Shift Overlap Shift Modifiers Downshifts
Coasting downshift
Part-throttle downshift
Detent downshift
Manual downshift

55. SHIFT VALVES
FIGURE 7-42 Shift overlap is the time period as the band releases and the direct clutch applies between second and third gears.

56. SHIFT VALVES
FIGURE 7-43 When a clutch is applied, fluid pressure keeps the exhaust check ball tightly seated (right). When the pressure is released, centrifugal force moves the check ball off its seat and allows a fluid flow out of the clutch (left).

57. SHIFT VALVES
FIGURE 7-44 Centrifugal force in the balance/release cavity (a) generates the same fluid force as that in the apply chamber (b). This balanced force allows the springs to return the piston and release the clutch.

58. SHIFT VALVES
TABLE 7-2 Shift Quality

59. SHIFT VALVES
FIGURE 7-45 The pressure rise in this servo is delayed as the accumulator strokes.

60. SHIFT VALVES
FIGURE 7-46 Clutch apply pressure seats the check ball so apply fluid must pass through the orifice (left). When the clutch releases, the check ball moves off it’s seat, allowing a faster clutch release because the fluid can bypass the orifice (right).

61. SHIFT VALVES
FIGURE 7-47 The manual valve has been moved to manual-2 to send line pressure to the 2–3 shift valve and governor plug. This moves both of them to the left and forces a downshift.

62. CVT HYDRAULIC CONTROL
Several hydraulic valves are used in a CVT to control the pulley positions and the fluid pressure for other systems:
Ratio control valve
Secondary pulley pressure
Reverse and, if used, forward clutch apply pressure
Torque converter clutch apply and release pressures
Lubrication pressure

63. CVT HYDRAULIC CONTROL
FIGURE 7-48 Movement of either the stepper motor or primary floating sheave will move the ratio control valve to add or remove fluid from the primary pulley. The secondary valve maintains the necessary pulley pressure on the drive belt.

64. CVT HYDRAULIC CONTROL
FIGURE 7-49 This pump is mounted off to the side and driven by a chain from the transmission input shaft.

65. CVT HYDRAULIC CONTROL
FIGURE 7-50 Always use the recommended CVT fluid in CVT transmissions.

66. SUMMARY
An automatic transmission monitors vehicle load and speed to determine shift timing and quality.
Various types of valves are used to direct the fluid flow and regulate the pressures used to operate the transmission.
The torque converter is a hydraulic coupling that connects the engine to the transmission. It also has a hydraulically operated lock-up clutch that, when applied, makes a mechanical connection between the engine and transmission.

67. SUMMARY
A governor valve is used to monitor vehicle speed, and a vacuum or mechanically controlled throttle valve regulates pressure that is applied to the ends of the shift valves to control when the shifts will occur.
Additional valves are used to control the shifts needed for other driving conditions. A kickdown valve is used to force a downshift, and shift-modifying valves are used to improve the quality and timing of both the upshifts and downshifts.

68. REVIEW QUESTIONS
Valves can be placed into three categories. What are they?
Servo valves are used to _________ another valve and switching valves are used to _________ flow.
The term exhaust when used with an automatic transmission means that the fluid is being directed to the _________ to empty a circuit.
The typical spring-balanced pressure regulator valve maintains mainline pressure at about _________ to _________ psi.
Under certain driving conditions, _________ pressure will increase and be used to _________ mainline pressure.
Full-throttle pressure will increase mainline pressure to about _________ to _________ psi.

69. REVIEW QUESTIONS
Mainline pressure in reverse should be between _________ and _________ psi.
The torque converter must have continual flow to maintain _________ temperature.
Typical torque converter pressure is _________ to _________ psi.
Most lock-up torque converters are controlled _________ by the ECM.
Fluid leaving the torque converter is directed to the _________ exchanger.
Fluid returning from the heat exchanger is used to _________ the transmission.
Throttle valves are _________ regulating valves that provide a pressure _________ relative to the vehicle _________.
Throttle valves can be controlled by _________, _________, or _________ connections to the throttle linkage.

70. REVIEW QUESTIONS
As vehicle load _________, engine vacuum will _________, and throttle valve pressure will _________.
The detent valve is used to produce full-throttle pressure at _________ _________ _________.
The governor produces a signal that is proportionate to vehicle _________.
Shift valves are positioned by a spring and _________ pressure at one end and _________ pressure at the other end.
A coasting downshift results when _________ pressure drops.
A part-throttle downshift results because of a rise in _________ _________ pressure.

71. CHAPTER QUIZ Automatic transmission hydraulic pressure is created by
the pump.
the pressure regulator valve.
restrictions to fluid flow.
All of these

72. CHAPTER QUIZ Automatic transmission hydraulic pressure is created by
the pump.
the pressure regulator valve.
restrictions to fluid flow.
All of these

73. CHAPTER QUIZ
2. Three categories of valves found in a hydraulic circuit are
switching, servo, and pressure regulating.
accumulator, flow control, and pressure regulating.
switching, manual, and flow control.
manual, shift, and accumulator.

74. CHAPTER QUIZ
2. Three categories of valves found in a hydraulic circuit are
switching, servo, and pressure regulating.
accumulator, flow control, and pressure regulating.
switching, manual, and flow control.
manual, shift, and accumulator.

75. CHAPTER QUIZ 3. Hydraulic diagrams are useful to trace the power flow.
trace the fluid flow.
understand the gear train.
All of these

76. CHAPTER QUIZ 3. Hydraulic diagrams are useful to trace the power flow.
trace the fluid flow.
understand the gear train.
All of these

77. CHAPTER QUIZ 4. A switching valve can be moved hydraulically.
mechanically.
by another valve.
All of these

78. CHAPTER QUIZ 4. A switching valve can be moved hydraulically.
mechanically.
by another valve.
All of these

79. CHAPTER QUIZ 5. Normal unboosted line pressure is about _________ psi.
10 to 15
25 to 35
50 to 60
125 to 135

80. CHAPTER QUIZ 5. Normal unboosted line pressure is about _________ psi.
10 to 15
25 to 35
50 to 60
125 to 135

81. CHAPTER QUIZ
6. Student A says that most pressure regulator valves are arranged so that line pressure tries to move the valve in one direction while a spring tries to move the valve in the other. Student B says that most pressure regulator valves are arranged so line pressure tries to move the valve in one direction while boost valve pressure tries to move the valve in the other. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

82. CHAPTER QUIZ
6. Student A says that most pressure regulator valves are arranged so that line pressure tries to move the valve in one direction while a spring tries to move the valve in the other. Student B says that most pressure regulator valves are arranged so line pressure tries to move the valve in one direction while boost valve pressure tries to move the valve in the other. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

83. CHAPTER QUIZ 7. An increase in mainline pressure is desirable to
produce firmer shifts.
improve shift feel.
increase holding power.
All of these

84. CHAPTER QUIZ 7. An increase in mainline pressure is desirable to
produce firmer shifts.
improve shift feel.
increase holding power.
All of these

85. CHAPTER QUIZ 8. Fluid is directed to the torque converter by the
pressure regulator.
manual valve.
pump.
boost valve.

86. CHAPTER QUIZ 8. Fluid is directed to the torque converter by the
pressure regulator.
manual valve.
pump.
boost valve.

87. CHAPTER QUIZ
9. In many transmissions, torque converter clutch lock-up occurs when the
fluid flow through the converter is reversed.
fluid flow to the cooler is shut off.
converter pressure is raised to 125 psi.
All of these

88. CHAPTER QUIZ
9. In many transmissions, torque converter clutch lock-up occurs when the
fluid flow through the converter is reversed.
fluid flow to the cooler is shut off.
converter pressure is raised to 125 psi.
All of these

89. CHAPTER QUIZ 10. The transmission cooler is usually located in the
oil pan.
coolest tank of the radiator.
area in front of the air-conditioning condenser.
hottest part of the radiator.

90. CHAPTER QUIZ 10. The transmission cooler is usually located in the
oil pan.
coolest tank of the radiator.
area in front of the air-conditioning condenser.
hottest part of the radiator.

91. CHAPTER QUIZ
11. An automatic transmission can be damaged by towing a vehicle because
it will not be lubricated unless the engine is running.
the torque converter will seize up.
the clutches and bands will not apply.
All of these

92. CHAPTER QUIZ
11. An automatic transmission can be damaged by towing a vehicle because
it will not be lubricated unless the engine is running.
the torque converter will seize up.
the clutches and bands will not apply.
All of these

93. CHAPTER QUIZ
12. A supplemental transmission cooler should typically be installed
before the heat exchanger.
after the heat exchanger.
behind the radiator.
behind the condenser.

94. CHAPTER QUIZ
12. A supplemental transmission cooler should typically be installed
before the heat exchanger.
after the heat exchanger.
behind the radiator.
behind the condenser.

95. CHAPTER QUIZ 13. The throttle valve is used to sense vehicle speed.
engine load.
engine speed.
transmission load.

96. CHAPTER QUIZ 13. The throttle valve is used to sense vehicle speed.
engine load.
engine speed.
transmission load.

97. CHAPTER QUIZ 14. Higher throttle openings cause the transmission to
shift at higher speeds.
produce firmer upshifts.
increase the line pressure.
All of these

98. CHAPTER QUIZ 14. Higher throttle openings cause the transmission to
shift at higher speeds.
produce firmer upshifts.
increase the line pressure.
All of these

99. CHAPTER QUIZ 15. The governor valve is used to sense vehicle speed.
engine load.
engine speed.
transmission load.

100. CHAPTER QUIZ 15. The governor valve is used to sense vehicle speed.
engine load.
engine speed.
transmission load.

101. CHAPTER QUIZ
16. A vacuum modulator transmission also has a throttle-controlled valve that can produce
reduced line pressure.
full-throttle downshifts.
slightly earlier shift timing.
All of these

102. CHAPTER QUIZ
16. A vacuum modulator transmission also has a throttle-controlled valve that can produce
reduced line pressure.
full-throttle downshifts.
slightly earlier shift timing.
All of these

103. CHAPTER QUIZ 17. A stronger spring in the vacuum modulator produces
less part-throttle line pressure.
greater part-throttle line pressure.
earlier upshifts.
softer upshifts.

104. CHAPTER QUIZ 17. A stronger spring in the vacuum modulator produces
less part-throttle line pressure.
greater part-throttle line pressure.
earlier upshifts.
softer upshifts.

105. CHAPTER QUIZ
18. Student A says that the manual valve position is controlled by the shift lever. Student B says that the manual valve position is controlled by a detent cam and spring-loaded ball or roller. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

106. CHAPTER QUIZ
18. Student A says that the manual valve position is controlled by the shift lever. Student B says that the manual valve position is controlled by a detent cam and spring-loaded ball or roller. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

107. CHAPTER QUIZ 19. The pressure signal from the governor is used to
produce higher line pressure at higher speeds.
move the shift valves to the upshift position.
produce firmer shifts at higher speeds.
move the shift valves with the vehicle stopped.

108. CHAPTER QUIZ 19. The pressure signal from the governor is used to
produce higher line pressure at higher speeds.
move the shift valves to the upshift position.
produce firmer shifts at higher speeds.
move the shift valves with the vehicle stopped.

109. CHAPTER QUIZ
20. Student A says that as the speed increases, centrifugal force acting on the governor weights will move the valve to increase governor pressure. Student B says that as the speed increases, centrifugal force acting on the governor weights will balance the output shaft to prevent vibrations. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

110. CHAPTER QUIZ
20. Student A says that as the speed increases, centrifugal force acting on the governor weights will move the valve to increase governor pressure. Student B says that as the speed increases, centrifugal force acting on the governor weights will balance the output shaft to prevent vibrations. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

111. CHAPTER QUIZ
21. Most shift valves use _________ to move them to a downshift position when the vehicle stops.
throttle pressure
governor pressure
spring pressure
Any of these

112. CHAPTER QUIZ
21. Most shift valves use _________ to move them to a downshift position when the vehicle stops.
throttle pressure
governor pressure
spring pressure
Any of these

113. CHAPTER QUIZ
22. When a shift valve moves against the spring pressure, the transmission will
upshift.
downshift.
increase the line pressure.
shift to neutral.

114. CHAPTER QUIZ
22. When a shift valve moves against the spring pressure, the transmission will
upshift.
downshift.
increase the line pressure.
shift to neutral.

115. CHAPTER QUIZ
23. Student A says that an accumulator is used to reduce fluid pressure in a servo that is applying to produce a softer upshift. Student B says that an orifice is used to reduce fluid pressure in a servo that is applying to produce a softer upshift. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

116. CHAPTER QUIZ
23. Student A says that an accumulator is used to reduce fluid pressure in a servo that is applying to produce a softer upshift. Student B says that an orifice is used to reduce fluid pressure in a servo that is applying to produce a softer upshift. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

117. CHAPTER QUIZ
24. Student A says that an orifice will cause a fluid pressure drop when fluid is flowing through it. Student B says that an orifice will have no effect on fluid pressure if there is no flow. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

118. CHAPTER QUIZ
24. Student A says that an orifice will cause a fluid pressure drop when fluid is flowing through it. Student B says that an orifice will have no effect on fluid pressure if there is no flow. Who is correct?
Student A
Student B
Both A and B
Neither A nor B

119. CHAPTER QUIZ 25. A manual-1 downshift above 30 mph can cause the
engine to overrev.
transmission to shift into second.
transmission to shift into neutral.
vehicle to set off an alarm.

120. CHAPTER QUIZ 25. A manual-1 downshift above 30 mph can cause the
engine to overrev.
transmission to shift into second.
transmission to shift into neutral.
vehicle to set off an alarm.