Dodge Durango (DN). Manual — part 122
starts must not be possible in any other gear posi-
tion.
(3) With shift lever handle in:
(a) PARK position—Apply forward force on cen-
ter of lever and remove pressure. Engine starts
must be possible.
(b) PARK position—Apply rearward force on cen-
ter of lever and remove pressure. Engine starts
must be possible.
(c) NEUTRAL position—Normal position. Engine
starts must be possible.
(d) NEUTRAL position—Engine
running
and
brakes applied, apply forward force on center of
shift lever. Transmission shall not be able to shift
from neutral to reverse.
ROAD TESTING
Before road testing, be sure the fluid level and con-
trol
cable
adjustments
have
been
checked
and
adjusted if necessary. Verify that all diagnostic trou-
ble codes have been resolved.
Observe engine performance during the road test.
A poorly tuned engine will not allow accurate analy-
sis of transmission operation.
Operate the transmission in all gear ranges. Check
for shift variations and engine flare which indicates
slippage. Note if shifts are harsh, spongy, delayed,
early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means
clutch or overrunning clutch problems.
A slipping clutch can often be determined by com-
paring which internal units are applied in the vari-
ous gear ranges. The Clutch Application chart
provides a basis for analyzing road test results.
CLUTCH APPLICATION CHART
SLP
UD
OD
R
2C
4C
L/R
OVERRUNNING
P–PARK
ON
R–REVERSE
ON
ON
N-NEUTRAL
ON
D–OVERDRIVE
FIRST
ON
ON*
ON
SECOND
ON
ON
SECOND PRIME
ON
ON
THIRD
ON
ON
FOURTH
ON
ON
LIMP-IN
ON
ON
2–FIRST
ON
ON*
ON
SECOND
ON
ON
LIMP-IN
ON
ON
1–LOW
ON
ON
ON
*L/R clutch is on only with the output shaft speed below 150 rpm.
HYDRAULIC PRESSURE TEST
An accurate tachometer and pressure test gauges
are required. Test Gauge C-3293-SP has a 300 psi
range and is used at all locations where pressures
exceed 100 psi.
Pressure Test Port Locations
Only two pressure ports are supplied on the trans-
mission case. The torque converter ON and torque
converter OFF ports are located on the right side of
the transmission case (Fig. 30).
To determine the line pressure, there are two avail-
able methods. The DRB scan tool can be used to read
line pressure from the line pressure sensor. The sec-
ond method is to install Line Pressure Adapter 8259
(Fig. 32) into the transmission case and then install
the pressure gauge and the original sensor into the
adapter. This will allow a comparison of the DRB
readings and the gauge reading to make a determi-
nation regarding the accuracy of the feedback con-
trols.
21 - 354
45RFE AUTOMATIC TRANSMISSION
DN
DIAGNOSIS AND TESTING (Continued)
In order to access any other pressure tap locations,
the transmission oil pan must be removed, the pres-
sure port plugs removed and Valve Body Pressure
Tap Adapter 8258 (Fig. 33) installed. The extensions
supplied with Adapter 8258 will allow the installa-
tion of pressure gauges to the valve body. Refer to
(Fig. 31) for correct pressure tap location identifica-
tion.
TEST PROCEDURE
All pressure readings should be taken with the
transmission fluid level full, transmission oil at the
normal operating temperature, and the engine at
1500 rpm. Check the transmission for proper opera-
tion in each gear position that is in question or if a
specific element is in question, check the pressure
readings in at least two gear positions that employs
that element. Refer to the Hydraulic Schematics at
the rear of this section to determine the correct pres-
sures for each element in a given gear position.
NOTE: The 45RFE 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
shifts except the 3–4, 4–3, and 4–2prime shifts is 120
Fig. 30 Torque Converter Pressure Locations
Fig. 31 Pressure Tap Locations
Fig. 32 Line Pressure Adapter 8259
Fig. 33 Valve Body Pressure Tap Adapter 8258
DN
45RFE AUTOMATIC TRANSMISSION
21 - 355
DIAGNOSIS AND TESTING (Continued)
psi. The upshift/downshift pressure for the 3–4, 4–3,
and the 4–2prime shifts is 100 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 TESTING 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 (Fig. 34).
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.
CONVERTER HOUSING FLUID LEAK
DIAGNOSIS
When diagnosing converter housing fluid leaks,
two items must be established before repair.
(1) Verify that a leak condition actually exists.
(2) Determined the true source of the leak.
Some suspected converter housing fluid leaks may
not be leaks at all. They may only be the result of
residual fluid in the converter housing, or excess
fluid spilled during factory fill or fill after repair.
Converter
housing
leaks
have
several
potential
sources. Through careful observation, a leak source
can be identified before removing the transmission
for repair. Pump seal leaks tend to move along the
drive hub and onto the rear of the converter. Pump
cover O-ring leaks follow the same path as a seal
leak.
TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
(1) Leaks at the weld joint around the outside
diameter weld (Fig. 35).
(2) Leaks at the converter hub weld (Fig. 35).
SERVICE PROCEDURES
FLUID LEVEL CHECK
Low fluid level can cause a variety of conditions
because it allows the pump to take in air along with
the fluid. As in any hydraulic system, air bubbles
make the fluid spongy, therefore, pressures will be
low and build up slowly.
Improper filling can also raise the fluid level too
high. When the transmssion has too much fluid, the
geartrain churns up foam and cause the same condi-
tions which occur with a low fluid level.
In either case, air bubbles can cause overheating
and/or fluid oxidation, and varnishing. This can
interfere with normal valve, clutch, and accumulator
operation. Foaming can also result in fluid escaping
from the transmission vent where it may be mis-
taken for a leak.
Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
and is contaminated with metal or friction material
particles, a complete transmission recondition is
needed. Be sure to examine the fluid on the dipstick
Fig. 34 Air Pressure Test Passages
Fig. 35 Converter Leak Points—Typical
1 – OUTSIDE DIAMETER WELD
2 – TORQUE CONVERTER HUB WELD
3 – STARTER RING GEAR
4 – LUG
21 - 356
45RFE AUTOMATIC TRANSMISSION
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DIAGNOSIS AND TESTING (Continued)
closely. If there is any doubt about its condition,
drain out a sample for a double check.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
The transmission fluid level should be inspected at
least every six months.
FLUID LEVEL CHECK PROCEDURE
The transmission has a dipstick to check oil level.
It is located on the right side of the engine. Be sure
to wipe all dirt from dipstick handle before removing.
The torque converter fills in both the P Park and N
Neutral positions. Place the selector lever in P Park
to be sure that the fluid level check is accurate. The
engine should be running at idle speed for at
least one minute, with the vehicle on level
ground. At normal operating temperature (approxi-
mately 82 C. or 180 F.), the fluid level is correct if it
is in the HOT region (cross-hatched area) on the oil
level indicator. The fluid level will be approximately
at the upper COLD hole of the dipstick at 70° F fluid
temperature.
NOTE: Engine and Transmission should be at nor-
mal operating temperature before performing this
procedure.
(1) Start engine and apply parking brake.
(2) Shift the transmission into Drive for approxi-
mately 2 seconds.
(3) Shift the transmission into Reverse for approx-
imately 2 seconds.
(4) Shift the transmission into Park.
(5) Hook up DRBIII scan tool and select transmis-
sion.
(6) Select sensors.
(7) Read the transmission temperature value.
(8) Compare the fluid temperature value with the
chart.
(9) Adjust transmission fluid level shown on the
dipstick according to the chart.
NOTE: After adding any fluid to the transmission,
wait a minimum of 2 minutes for the oil to fully
drain from the fill tube into the transmission before
rechecking the fluid level.
(10) Check transmission for leaks.
FLUID AND FILTER REPLACEMENT
Refer to the Maintenance Schedules in Group 0,
Lubrication and Maintenance, for proper service
intervals. The fluid capacity of the 45RFE is approx-
imately 13.25 liters (14.0 quarts).
Transmission Fluid Temperature Chart
DN
45RFE AUTOMATIC TRANSMISSION
21 - 357
SERVICE PROCEDURES (Continued)
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