Daewoo Korando. Manual - part 251

AUTOMATIC TRANSMISSION  5A-47

POWER FLOWS

INTRODUCTION

The power flows for the various transmission selections are listed below:

l

Power Flow - Neutral and Park

l

Power Flow - Reverse

l

Power Flow - Manual 1

l

Power Flow - Drive 1

l

Power Flow - Drive 2

l

Power Flow - Drive 3

l

Power Flow - Drive 3 Lock Up

l

Power Flow - Drive 4 (Overdrive)

l

Power Flow - Drive4 Lock Up

Each power flow is described in the following sections.

Table 5.1 details the engaged elements versus the gear selected for all transmission selections.

Gear State

Park and Neutral

Reverse

Manual 1

Drive 1

Drive 2 and Manual 2

Drive 3 and Manual 3

Drive 3 Lock Up and

Manual 3 Lock Up

Drive 4 Overdrive

Drive 4 Lock Up

C1

-

-

-

-

-

X

X

X

X

C2

-

-

X

X

X

X

X

X

X

C3

-

X

-

-

-

-

-

-

-

C4

-

-

X

-

X

X

X

-

-

B1

-

-

-

-

X

-

-

-

-

B2

X

X

X

-

-

-

-

-

-

1-2

OWC

-

-

-

X

-

-

-

-

-

3-4

OWC

-

-

X

X

X

X

X

-

-

LU

CLUTCH

-

-

-

-

-

-

X

-

X

ELEMENTS ENGAGED

Figure 5.1 - Engaged Elements vs Gear Selected

Planetary Gear Set

5A-48  AUTOMATIC TRANSMISSION

POWER FLOW - PARK AND NEUTRAL

In Park and Neutral, there is no drive to the planetary gear set. The rear band is applied to eliminate ‘clunk’ on
engagement of the reverse gear, and to improve the low range engagement for 4WD applications. No other clutches
or bands are applied.

In Park the transmission is mechanically locked by engaging a case mounted pawl with teeth on the output shaft ring
gear.

Control

To maintain this arrangement in the steady state solenoids and valves are activated as follows:

l

Solenoids S1 and S2 are switched off.

l

Line (pump) pressure is applied to the primary regulator valve (PRV) and to the solenoid supply valve.

l

The converter, oil cooler, and lubrication circuits are charged from the primary regulator valve.

l

The line 500 circuit is charged by the solenoid supply valve.

l

The S5 circuit is charged by the variable pressure solenoid (S5).

l

Line pressure is prevented from entering the drive circuit by the manual valve.

l

The B1 circuit and all clutch circuits are open to exhaust.

Refer to figure 5.1 and table 5.2.

Table 5.2 - Engaged Elements - Park arid Neutral

Gear State

Park and Neutral

C1

-

C2

-

C3

-

C4

-

B1

-

B2

X

1-2

OWC

-

3-4

OWC

-

LU

CLUTCH

-

ELEMENTS ENGAGED

AUTOMATIC TRANSMISSION  5A-49

POWER FLOW - REVERSE

In Reverse, transmission drive is via the input shaft and the forward clutch cylinder to the hub of the C3 clutch. The
elements of the transmission function as follows :

l

The C3 clutch is engaged and drives the reverse sun gear in a clock-wise direction.

l

The B2 band is engaged and holds the planetary gear carrier stationary causing the long pinion to rotate anti-
clockwise about its axis on the pinion shaft.

l

The long pinion drives the internal ring fear in the same direction.

l

The internal ring being splined to the output shaft drives it in an anti-clockwise or reverse direction.

Control

To maintain this arrangement in the steady state

solenoids and valves are activated as follows:

l

Solenoids S1 and S2 are switched off.

l

Line pressure is directed through the reverse lockout valve to both the inner and outer apply areas of the rear
servo piston for B2 band application.

l

Line pressure feeds the reverse oil circuit via the manual valve.

l

Reverse oil is routed from the manual valve to the C3 clutch.

l

Reverse oil is also applied to the spring end of the primary regulator valve to assist the spring and to boost the
line pressure value.

l

All other clutch and band apply circuits are open to exhaust.

Refer to figure 5.2 and table 5.3

Table 5.3 - Engaged Elements - Reverse

Gear State

Reverse

C1

-

C2

-

C3

X

C4

-

B1

-

B2

X

1-2

OWC

-

3-4

OWC

-

LU

CLUTCH

-

ELEMENTS ENGAGED

5A-50  AUTOMATIC TRANSMISSION

POWER FLOW - MANUAL 1

In Manual 1, transmission drive is via the input shaft

to the forward clutch cylinder. The elements of the

transmission function as follows :

l

The C2 clutch is engaged to drive the forward sun gear, via the 3-4 OWC.

l

The B2 band is engaged to hold the planetary gear carrier stationary.

l

The forward sun gear drives the short pinion anti-clockwise.

l

The short pinion drives the long pinion clockwise.

l

The long pinion rotating about its axis drives the internal ring gear and the output shaft in a clockwise or

forward direction.

l

The C4 clutch provides engine braking through the 3-4 OWC on overrun.

Control

To maintain this arrangement in the steady state solenoids and valves are activated as follows:

l

Solenoids S1 and S2 are switched ON.

l

The 1-2,2-3, and 34 shift valves are held in their first gear positions by line 500 pressure.

l

Drive (line pressure) oil from the manual valve engages the C2 clutch.

l

Lo-1st (line pressure) oil is routed through the 1-2 shift valve to the C4 clutch, and to the inner apply area of
the rear servo piston for B2 band application.

Refer to figure 5.3 and table 5.4.

Table 5.4 - Engaged Elements - Manual 1

Gear State

Manual 1

C1

-

C2

X

C3

-

C4

X

B1

-

B2

X

1-2

OWC

-

3-4

OWC

X

LU

CLUTCH

-

ELEMENTS ENGAGED