Land Rover Lesson 2 Auto Trans Coolingine Rover Manual

Spool Valves
The valve block contains twenty one spool valves which
control various functions of the transmission. The spool
valves are of conventional design and are operated by
fluid pressure.
Each spool valve is located in its spool bore and held
in a default (unpressurised) position by a spring. The
spool bore has a number of ports which allow fluid to
flow to other valves and clutches to enable transmission
operation. Each spool has a piston which is waisted to
allow fluid to be diverted into the...

PLANETARY GEAR TRAINS
The planetary gear trains used on the 6HP26
transmission comprise a single web planetary gear train
and a double web planetary gear train. These gear trains
are known as Lepelletier type gear trains and together
produce the six forward gears and the one reverse gear.
Single Web Planetary Gear Train
The single web planetary gear train comprises:
•One sunwheel
•Three planetary gears
•One planetary gear carrier
•One ring gear or annulus
Cylinder1
Baffle plate2
Ring gear3
Planetary...

Double Web Planetary Gear Train
Planetary gear spider1
Planetary gears (short)2
Ring gear3
Output shaft4
Planetary gear5
Sunwheel6
Double planetary gears (long)7
Sunwheel8
The double planetary gear train comprises:
•Two sunwheels
•Three short planetary gears
•Three long planetary gears
•One planetary gear carrier
•One ring gear or annulus
POWER FLOWS
Operation of the transmission is controlled by the TCM
which electrically activates various solenoids to control
the transmission gear selection. The...

Powerflow Schematic
Torque input from engine1
Torque converter lock-up clutch2
Single web planetary gear carrier3
Single web planetary gears4
Single web sunwheel 15
Double web sunwheel 26
Double web planetary gears - Long7
Double web planetary gear carrier8
Double web planetary gears - Short9
Double web sunwheel 310
Torque output from transmission11
Multiplate clutchA
Multiplate clutchB
Multiplate brakeC
Multiplate brakeD
Multiplate clutchE
Engine torque is transferred, via operation of single or...

Electronic Pressure Regulator Solenoids (EPRS)Shift Control
Solenoid Valve
Gear Selector Lever
Position654321
-ON-ONP
-ON-ONONR
-ON-ONN
-ON--ON-ONOND 1
-ON--ON-ONOND 2
-ON--ON-ONOND 3
-ON--ON-ONONOND 4
-ON--ON-ONONOND 5
-ON--ON-ONONOND 6
ON = Active (pressure build up)
OFF = Inactive
-ON- = Inactive (pressure drain)
The following table shows which clutches are operating
for selected gear ratios to produce the required torque
output from the transmission.
BrakeClutchShift Control
Solenoid Valve
Gear...

Shift Elements
Turbine shaft1
Stator shaft2
Single web planetary gear train3
Ring gear 14
Clutch A5
Clutch B6
Clutch E7
Brake clutch C8
Fixed connection to transmission housing9
Shaft key10
Brake clutch D11
Double web planetary gear train12
Planetary gears - Long13
Ring gear 214
Sunwheel 215
Sunwheel 316
Double web planetary gear carrier17
Planetary gears - short18
Single web planetary gear carrier19
Sunwheel 120
The shift elements are three rotating multiplate clutches
(A, B and E) and two fixed...

Power Flow 1st Gear
The gear selector lever and the manual selector valve
spool are in the D position. Engine torque is transmitted
from the torque converter turbine shaft to the ring gear
1 of the single web planetary gear train and the outer
plate carrier of clutch E.
Ring gear 1 drives the planetary gears which rotate
around sunwheel 1. This drives the planetary gear carrier
1 and also the outer plate carrier of clutch A and the
inner plate carrier of clutch B.
When clutch A is engaged, sunwheel 3 in...

NOTE: Refer to Shift Elements illustration for key
Power Flow 2nd Gear
(G421157) Technical Training272
Lesson 2 – PowertrainAutomatic Transmission 

The gear selector lever and the manual selector spool
valve are in the D position. Engine torque is transmitted
from the torque converter turbine shaft to the ring gear
1 of the single web planetary gear train and the outer
plate carrier of clutch E.
Ring gear 1 drives the planetary gears which rotate
around sunwheel 1. This drives the planetary gear carrier
1 and also the outer plate carrier of clutch A and the
inner plate carrier of clutch B.
When clutch A is engaged, sunwheel 3 in the double
web...

Power Flow 3rd Gear
The gear selector lever and the manual selector spool
valve are in the D position. Engine torque is transmitted
from the torque converter turbine shaft to the ring gear
1 of the single web planetary gear train and the outer
plate carrier of clutch E.
Ring gear 1 drives the planetary gears which rotate
around sunwheel 1. This drives the planetary gear carrier
1 and also the outer plate carrier of clutch A and the
inner plate carrier of clutch B.
When clutch A is engaged, sunwheel 3 in...