2007 KIA CARNIVAL Workshop Manual

D 4th gear

Reverse

2007 > 2.7L V6 GASOLINE >
Description
The automatic transmission is a combination of 3 - element 2 - phase 1 - stage torque converter and double shaft
electrocally - controlled unit which provides 4 speeds forward and 1 reverse. To improve the efficiency of power
transmission, the line pressure control was changed applying “Variable Force Solenoid (VFS) valve” on this model.
However, adopting VFS on this model, the line pressure is variably changed according to TPS and the vehicle speed,
this will enable more improved efficiency of power transmission and fuel consumption.
Characteristics
Some of the characteristics include:
▶Different power transfer
▶Different component layout
▶New shift logic(HIVEC) to improve shift feeling
▶Position of Valve Body
▶Variable shift pattern
▶Communication protocol and method
▶Step gate type shift lever.
Item Details
Weight Reduction 1. Aluminum oil pump
a. 2.3kg Approx
2. Pressed parts a. Retainer and hub of brakes and clutches
b. Carrier of planetary gear set
Better shift quality 1. Independent control of clutches and brakes enabled better control of
hydraulic pressure and skiped shifts (4 to 2, 3 to 1)
2. During N to D or N to R shift, feedback control adopted.
3. When starting from Creep condition, reduction of shock.(Creep condition is
controlled with 1st gear)
4. Solenoid valve frequency is increased for more accurate control. 35Hz to
61.3Hz except DCCSV that is 35Hz and VFS that is 600Hz.
5. HIVEC adoption for better shift feeling.
6. Variable shift pattern.
Increase in Power train efficiency 1. Fully Variable Line Pressure
2. VFS(Variable Force Solenoid)
- Manual shifting possible
- Step gate type shift lever

Dynamic drive by sports mode

MECHANICAL SYSTEM
OPERATION COMPONENTS AND FUNCTIONOperating Element Symbol Function
Under drive clutch UDConnect input shaft and under drive sun gear
Reverse clutch REVConnect input shaft and reverse sun gear
Overdrive clutch ODConnect input shaft and over drive carrier

Low&Reverse brakeLRHold LR annulus gear and OD carrier
Second brake 2NDHold reverse sun gear
One way clutch OWCRestrict the rotating direction of low & reverse annulus gear
Operating elements
UD/COD/CREV/C 2ND/B LR/BOWC
P ●
R ●●
N ●
D1 ● ●○
D2 ● ●
D3 ●●
D4 ●●
1) ○ : OWC is operated when shifts from 1st gear to 2nd gear.
2) L&R brake is released in 1st gear when the vehicle speed is more than 5KPH approximately.
Torque converter and shaft
The torque converter consists of an impeller(pump), turbine and stator assembly in a single unit. The pump is
connected to the engine crankshaft and turns as the engine turns. This drawing force is transmitted to the turbine
through the oil which is recycled by the stator.
The transmission has two parallel shafts ; the input shaft and the output shaft. Both shafts are in line with the engine
crankshaft. The input shaft includes the overdrive clutch, reverse clutch, underdrive clutch, one way clutch, 2ND brake,
low&reverse brake, overdrive planetary carrier, output planetary carrier and transfer drive gear. The output shaft
includes the transfer driven gear.
CLUTCHES
The gear changing mechanism utilizes three multi- disc clutches. The retainers of these clutches are fabricated from
high- precision sheet metal for lightness and ease of production. Also, more responsive gearshifts at high engine
speeds are achieved by a pressure- balanced piston mechanism that cancels out centrifugal hydraulic pressure. This
mechanism replaces the conventional ball check valve.
UNDERDRIVE CLUTCH
The underdrive clutch operates in 1st, 2nd, and 3rd gears and transmits driving force from the input shaft to the
underdrive sun gear(A).
The components comprising the under clutch are as illustrated below.

Hydraulic pressure acts in the piston pressure chamber(B) (between the piston(c) and retainer) and thus pushes the
piston(C). In turn, the piston depresses the clutch discs and thereby transmits driving force from the retainer(D) to the
hub(E) side.
At high speed, fluid remaining in the piston pressure chamber is subjected to centrifugal force and attempts to push
the piston.
However, fluid in the balance fluid chamber(A) (the space between the piston and return spring retainer(B)) is also
subjected to centrifugal force.
Thus, the hydraulic pressure on one side of the piston cancels out the hydraulic pressure on the other side, and the
piston does not move.
REVERSE CLUTCH AND OVERDRIVE CLUTCH
The reverse clutch(C) operates when the reverse gear is selected and transmits driving force from the input shaft to
the reverse sun gear.
The overdrive clutch(D) operates in 3rd and 4th gears and transmits driving force from the input shaft to the overdrive
planetary carrier and low- reverse annulus gear.