Figure 44
PRESSURE REGULATOR VALVE (1992 2ND DESIGN, 1993 & UP )
LINE PRESS CONT
LUBE
UNFL
T
LINE
CONV
FEED
UNFL
T
LINE
ORIF LINE
EX
The pressure regulator valve controls line pressure to
provide the correct pressure to apply clutches, supply lube
and apply TCC. The valve exhausts line pressure to the
lube or converter clutch apply circuit to reduce line
pressure to a required operating pressure. If operating
conditions require a higher pressure, as in high load, the
regulator will exhaust less and line pressure will increase.
The pressure regulator contains the pressure regulator
valve, line pressure control plunger, and pressure regulator
spring which are the main components that control line
pressure.
On initial start up the pressure regulator is bottomed in the
bore by spring and line pressure control pressure. At this
time no pressure is being exhausted until orificed line
pressure increases enough to cause the regulator valve to
move against spring pressure. As the regulator valve
moves against spring pressure line pressure is exhausted to
lube and converter clutch apply to control pressure.
PRESSURE REGULATOR VALVE 2nd DESIGN
At the same time that line pressure begins to act against
spring pressure, line pressure control from the line actuator
is applied to the line pressure control plunger to increase
force on the regulator valve in the same direction as the
spring. Line pressure is increased as pressure to the
pressure control plunger is increased by the line actuator.
When engine rpm is raised and lowered the regulator valve
and control plunger float back and forth against spring
pressure and line pressure control as a single unit. As rpm
begins to rise, pump output increases. The resulting line
pressure increase acting on the pressure regulator valve
forces the valve against spring and line pressure control to
the point where line pressure is exhausted. Line pressure
drops and the spring and line pressure control force the
valve back, blocking off exhaust. During normal operation
the valve continually maintains line pressure by moving
back and forth to exhaust.
31
AUTOMATIC TRANSMISSION SERVICE GROUP
Technical Service Information