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Description and Operation | Transaxle
Range Selection | Transaxle Shift Patterns
AX4N Transaxle Sectional View
Description and Operation
The AX4N automatic transaxle is a four-speed unit with electronic shift control. It is designed for operation in a transverse powertrain for front-wheel drive vehicles.
The AX4N automatic transaxle has the following major components:
- case with chain cover
- torque converter
- chain drive
- apply components:
-- two friction bands: overdrive, coast
-- five friction clutches: forward, direct, intermediate, reverse, low - intermediate
-- three one-way clutches: low, direct, low - intermediate
- two simple planetary gearsets:
- final drive planetary gearset
- pump assembly
- main control
Transaxle Range Selection--3.4L SHO
Vehicles equipped with the AX4N transaxle and a 3.0L (4V) or
3.4L SHO use a transmission control switch (TCS). The shift
quadrant has the following positions: P, R, N, D, 2 and 1.
No powerflow is transferred through the transaxle in PARK. A
parking pawl actuating rod assembly presses the parking pawl into
the park gear on the final drive sun gear. This locks the final
drive and prevents the vehicle from rolling. For safety reasons,
the parking brake should always be applied whenever the vehicle
Allows the vehicle to be operated in a rearward direction, at
a reduced gear ratio. Engine braking is provided in REVERSE.
As in PARK, there is no power transferred through the
transaxle in NEUTRAL. However, the final drive is not locked by
the parking pawl assembly, so the wheels are free to rotate. The
engine may be started in NEUTRAL.
This position provides all automatic shifts for first through fourth gears. This position also provides apply and release of the torque converter clutch (TCC). Coast braking occurs in third gear.
Fourth (OD) gear can be removed from the shift schedule by
depressing the transmission control switch (TCS) on the transaxle
range selector lever. Shift schedule status is displayed on the
instrument cluster by the transmission control indicator lamp
(TCIL) below the tachometer. If the TCIL display reads "O/D
OFF", overdrive has been removed from the shift schedule and
is not available. Depressing the TCS a second time restores
overdrive to the shift schedule.
This position provides second gear start. Application of the
torque converter clutch (TCC) may also occur in this range
depending on transaxle and vehicle conditions. This position can
be selected when starting on slippery roads for improved traction
or engine braking.
Provides a first gear hold after automatic or manual
downshift. The transaxle is prevented from downshifting into
first gear above a specific speed (approximately 48 km/h (30
mph)) to protect the powertrain from over-speeding. Engine
braking is provided in 1 position making it especially useful for
descending steep grades.
Transaxle Shift Patterns
Under certain conditions the transaxle will downshift
automatically to a lower gear range (without moving the transaxle
range selector lever). There are three categories of automatic
downshifts: coastdown, torque demand, and forced or kickdown
The coastdown downshift occurs as the name indicates, when the
vehicle is coasting down to a stop.
The torque demand downshift occurs (automatically) during part
throttle acceleration when the demand for torque is greater than
the engine can provide at that gear ratio. The transaxle will
disengage the torque converter clutch to provide added
acceleration, if applied.
For maximum acceleration, the driver can force a downshift by
pressing the accelerator pedal to the floor. A forced downshift
into second gear is possible below 105 km/h (65 mph). Below
approximately 48 km/h (30 mph) a forced kickdown to first gear
will occur. For all shift speeds, specifications are subject to
variation due to tire size and engine calibration requirements.
AX4N Automatic Transaxle--Sectional View
|2||--||Forward Clutch Assy|
|3||--||Direct Clutch Assy|
|4||--||Intermediate Clutch Assy|
|5||--||Reverse Clutch Assy|
|6||--||Low/Intermediate Clutch Assy|
|7||7A153||Final Drive Ring Gear|
|8||--||Final Drive Gearset (Part of 7F465)|
|10||7C190||Low/Intermediate One-Way Roller Clutch Assy|
|12||7H281||Coast Servo Piston|
|13||7D006||Rear Planetary Gearset|
|14||7A153||Rear Planetary Ring Gear|
|15||7A398||Front Planetary Gearset|
|17||7D171||Direct One-Way Roller Clutch Assy|
|18||7A089||Low One-Way Sprag Clutch|
|22||--||Pump Assy (Part of 7A100)|
|23||--||Reactor (Part of 7902)|
|24||--||Impeller (Part of 7902)|
|25||--||Turbine (Part of 7902)|