SsangYong Musso. Manual - part 470
AUTOMATIC TRANSMISSION 5A-57
POWER FLOW - DRIVE 4 (OVERDRIVE)
In Drive 4 (Overdrive), transmission drive is via the input shaft to the forward clutch cylinder.
The elements of the transmission function as follows :
!
The C1 clutch is applied to drive the planet carrier clockwise.
!
The B1 band is applied to hold the reverse sun gear stationary.
!
As the planet carrier tuns, the long pinion ‘walks’ around the stationary reverse sun gear and rotates around its
axis driving the internal ring gear and output shaft in a clockwise or forward direction at a speed faster than the
input shaft i.e. in overdrive ratio.
!
The forward sun gear is also driven faster than the input shaft and overruns the 3-4 OWC.
!
The C2 clutch is engaged to reduce the speed differential across the 3-4 OWC.
Control
To maintain this arrangement in the steady state solenoids and valves are activated as follows:
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Solenoid S1 is switched On. S2 is switched Off.
!
With S1 switched On the 3-4 shift valve is held in the fourth gear position by line 500 pressure on the small end
of the valve.
!
With S2 switched Off the 2-3 shift valve is held in the fourth gear position by line 500 pressure on the large
end of the valve.
!
The 1-2 shift valve is held in the fourth gear position by S2 oil pressure.
!
2nd oil (line pressure) from the 1-2 shift valve is directed to the band apply regulator valve, and to the 2-3 shift
valve.
!
The band apply regulator valve supplies 2nd oil (regulated to line pressure multiplied by the valve ratio) to the
band apply feed (BAF) circuit.
!
Band apply feed oil is directed to:
- the outer apply area of the front servo
- the inner apply area of the front servo piston via the 3-4 shift valve
- the 1-2 shift valve to provide an exhaust port when the transmission is shifted to first gear
!
2nd oil at the 2-3 shift valve is directed to the 3rd oil circuit.
!
3rd oil from the 2-3 shift valve is directed to the clutch apply regulator valve, and to the 4-3 Sequence Valve.
!
The clutch apply regulator valve supplies oil (regulated to line 500 pressure multiplied by the valve ratio) to the
clutch apply feed (CAF) circuit.
!
The CAF oil is directed to:
- the C1 clutch
- the C1 bias valve
- the 4-3 sequence valve
!
Drive oil (line pressure) from the manual valve engages the C2 clutch
Refer to figure 5.8 and table 5.9.
Table 5.9 - Engaged Elements - Drive 4 (Overdrive)
Gear State
Drive 4 (Overdrive)
C1
X
C2
X
C3
-
C4
-
B1
X
B2
-
1-2
OWC
-
3-4
OWC
X
LU
CLUTCH
-
ELEMENTS ENGAGED