Air Checking Transmission Clutch Operation - Jeep KJ 2005 Service Manual

KJ
AUTOMATIC TRANSMISSION - 545RFE (Continued)
Fig. 3 Pressure Tap Locations
Fig. 4 Line Pressure Adapter 8259
1 - LINE PRESSURE SENSOR PORT
2 - LINE PRESSURE SENSOR
3 - TOOL 8259
4 - PRESSURE TAP
the rear of this section to determine the correct pres-
sures for each element in a given gear position.
NOTE: The 545RFE utilizes closed loop control of
pump line pressure. The pressure readings may
therefore vary greatly but should always follow line
pressure.
Some common pressures that can be measured to
evaluate pump and clutch performance are the
upshift/downshift pressures and the garage shift
pressures. The upshift/downshift pressure for all
AUTOMATIC TRANSMISSION - 545RFE
Fig. 5 Valve Body Pressure Tap Adapter 8258-A
1 - 545RFE TRANSMISSION
2 - TOOL 8258-A
shifts except the 4-5 shift is 120 psi. The upshift
pressure for the 4-5 shift is 130 psi. The garage shift
pressure when performing a N-R shift is 220 psi. The
garage shift pressure for the R-N and N-1 shifts is
120 psi.
AIR CHECKING TRANSMISSION CLUTCH
OPERATION
Air-pressure testing can be used to check transmis-
sion clutch operation. The test can be conducted with
the transmission either in the vehicle or on the work
bench, as a final check.
Air-pressure testing requires that the oil pan and
valve body be removed from the transmission. The
clutch apply passages are shown in the Air Pressure
Test Passages graphic (Fig. 6).
NOTE: The air supply which is used must be free of
moisture and dirt. Use a pressure of 30 psi to test
clutch operation.
Apply air pressure at each port. If the clutch is
functioning, a soft thump will be heard as the clutch
is applied. The clutch application can also be felt by
touching the appropriate element while applying air
pressure. As the air pressure is released, the clutch
should also release.
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