MITSUBISHI LANCER EVOLUTION X 2008 Workshop Manual
Page 201 of 241
GENERAL
BASIC BRAKE SYSTEM35A-2
GENERALM2350000100956
Brake systems with higher reliability and durability 
have achieved distinguished braking performance.
FEATURES
.
IMPROVEMENT OF BRAKING PERFOR-
MANCE
•A 10-inch single brake booster with the variable 
boost ratio mechanism has been used to assure 
maximum braking force with less pedal pressure 
in case of emergency. <Vehicles with ABS>
•In addition to the 10-inch single brake booster, a 
small and long stroke-type master cylinder has 
been adopted to achieve downsizing and secure 
assist force.
•15-inch or 16-inch ventilated disc brakes have 
been adopted for the front.
•8-inch leading trailing-type drum brake, 14-inch 
or 16-inch solid disc brake has been adopted for 
the rear.
.
IMPROVEMENT IN SAFETY
•The 4-wheel anti-lock brake system (4ABS) has 
been installed to prevent slippage resulting from 
the wheel lock and assure stable vehicle posture 
and driveability.<Vehicles with ABS>
•A rear wheel early lock-prevention proportioning 
valve has been used. <Vehicles without ABS>
•Electronic control braking force distribution sys-
tem (EBD) has been adopted to assure the maxi-
mum braking force independently of the 
passenger's position in the vehicle. <Vehicles 
with ABS>
•X-type piping of brake lines have been adopted 
for the front and rear wheels.
•Audible wear indicators are used on the front and 
rear brake pads to warn the driver of wear limit.
.
SERVICE QUALITY IMPROVEMENTS 
•Diagnostic function has been adopted to ABS for 
easier inspection. <Vehicles with ABS>
•Brake fluid reservoir, master cylinder, and brake 
booster have been integrated for downsizing and 
better serviceability. 
Page 202 of 241
GENERAL
BASIC BRAKE SYSTEM35A-3
<Vehicles without ABS>
<Vehicles with ABS>
AC609311AB
Brake booster
Master cylinder
Proportioning valve
Front disc brake
Reserve tank
Rear drum brake
Rear disc brake
AC609312AB
Brake booster
Master cylinder
Hydraulic unit
Front disc brake
Rear drum brake
Rear disc brake
Reserve tank 
Page 203 of 241
GENERAL
BASIC BRAKE SYSTEM35A-4
SPECIFICATIONS
ItemSpecifications
Master cylinderTy p eTandem type
I.D. mm (in)20.6 (0.81)
Brake boosterTy p eVacuum type, single
Effective dia. of power cylinder mm (in)254 (10.0)
Boost ratioVehicles without ABS6.5 (Pedal pressure: 188N)
Vehicles with ABS6.5 (Pedal pressure: 92N)
8.5 (Pedal pressure: 156N)
Rear wheel hydraulic control typeVehicles without ABSProportioning valves
Vehicles with ABSElectronic control braking force 
distribution system (EBD)
Front disc brakeTy p eVehicles with 16-inch wheelFloating caliper 1 piston 
ventilated disc (V5-S57)
Vehicles with 18-inch wheelFloating caliper 1 piston 
ventilated disc (V6-S57)
Disc effective dia × 
thickness mm (in)Vehicles with 16-inch wheel222 × 26 (8.7 × 1.02)
Vehicles with 18-inch wheel241.6 × 26 (9.5 × 1.02)
Cylinder I.D. mm (in)57.1 (2.25)
Pad thickness mm (in)10.0 (0.39)
Clearance adjustmentAutomatic adjustment
Rear drum brakeTy p eLeading trailing drum
Drum I.D. mm (in)203 (8.0)
Wheel cylinder I.D. mm (in)19.0 (0.75)
Lining thickness mm (in)4 (0.157)
Clearance adjustmentAutomatic
Rear disc brakeTy p eVehicles with 16-inch wheelFloating caliper 1 piston solid disc 
(S4-S35)
Vehicles with 18-inch wheelFloating caliper 1 piston solid disc 
(S6-S35)
Disc effective dia × 
thickness mm (in)Vehicles with 16-inch wheel226 × 10 (8.9 × 0.39)
Vehicles with 18-inch wheel258 × 10 (10.2 × 0.39)
Cylinder I.D. mm (in)34.9 (1.37)
Pad thickness mm (in)10.0 (0.39)
Clearance adjustmentAutomatic adjustment 
Page 204 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-5
CONSTRUCTION DESCRIPTION
MASTER CYLINDERM2350001000576
The master cylinder is a tandem type and is inte-
grated with the brake fluid reservoir with the level 
switch.
BRAKE BOOSTERM2350002000698
 A 10-inch single brake booster has been installed. 
The variable boost ratio mechanism which increases 
the brake booster gain has been adopted.
AC609255
AC609469 AC505913
AB
Primary piston assembly Secondary piston assembly Brake booster Master cylinderReserve tank
AC505931AB
Diaphragm
Reaction disc
Operating rod
Push rod
Barometric pressure chamber Booster return spring 
Page 205 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-6
VARIABLE BOOST RATIO MECHANISM
The variable boost ratio mechanism changes the input/output 
characteristics of the brake booster in two phases by changing 
the reaction force applied to the valve plunger during the assist 
phase.
.
AT INITIAL ASSISTING
1. When the brake pedal is not depressed (no input load 
applied), the reaction washer is not deformed.
2. When the brake pedal is depressed, the reaction washer is 
deformed to reach the ring piston and disc, then the first 
input characteristics begin (Ratio 1).
.
AT AN INCREMENT OF ASSIST RATIO
1. The reaction washer is further deformed and pushes down 
the ring piston and lock washer, deflecting the spring. All the 
force pushing the ring piston and disc is transferred to the 
brake pedal via spring seat and disc as the reaction force.
2. The reaction washer is then further deformed, and when the 
lock washer makes contact with the control housing, the 
input characteristics change. All the force applied from the 
reaction washer to the ring piston is now transferred to the 
control housing via the lock washer, so no force is applied to 
the brake pedal. The second input characteristics (Ratio 2) 
begin.
AC507766AB
Disc
Reaction
washer
Ring piston
AC507768AB
Valve
piston Spring
seat Spring
Lock washer
AC507769AB
Reaction
washer
Ring piston
Control
housing
Lock washer 
Page 206 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-7
BRAKE PEDALM2350007000422
The brake pedal retreat suppression mechanism that 
restraints the retraction of the brake pedal surface 
during a frontal collision has been adopted in order to 
reduce the shock to the driver's feet.When the brake booster is crushed rearward by the 
engine retreat during a frontal collision, the installa
-
tion surface of the brake pedal is retreated. In this 
case, the end of the pedal support is forcibly slid 
down and back by the interference with the slope 
mounted on the front deck crossmember assembly. 
At the same time, the linkage comprised of the pedal 
support, pedal arm, and push rod moves the brake 
pedal pad surface forward.
AC611958AB
Pedal support frame
position before collision 
Collision loadPedal retreat
path in collision <Before collision><After collision>
Brake booster
Brake pedal and support
memberSlopeBrake pedal and support
member
Slope
After the breakage
mechanism operates
Pedal support frame position after 
collision Brake booster
Pedal arm
Push
rodPush
rod
Pedal arm 
Page 207 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-8
FRONT BRAKEM2350003000602
Brakes with the following specifications have been 
adopted for the front brakes.
•The 1-piston ventilate disc brake (V5-S57 <Vehi-
cles with 16-inch wheel> or V6-S57 <Vehicles 
with 18-inch wheel>) has been adopted.
•An audible wear indicator that informs the driver 
of application limit has been adopted onto the 
front brake LH pads.
•The outer disc type brake disc which can be tight-
ened together with the wheel has been intro-
duced for better serviceability.
.
DISC BRAKE DESIGNATION
AC609316
AC201769
Wear indicator Brake discPad Normal
AB
At wear limit
<15-inch disc brake (V5-S57)>
<16-inch disc brake (V6-S57)>
No.ItemContents
1Brake disc typeV: Ventilated
S: Solid
2Brake size
(Minimum applicable 
disc wheel)
4: 14"
5: 15"
6: 16"
3Number of pistonsS: 1 (Floating type)
4Piston size
(Rounded integral 
value)
35: φ 34.9 mm
57: φ 57.1 mm
V  6  -  S  57
1        2               3          4
AC505124 
Page 208 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-9
REAR BRAKEM2350004000616
<Vehicles with rear drum brake>
8-inch leading trailing-type drum brakes have been 
adopted for the rear brakes in order to provide stable 
braking force at all times both when moving forward 
and reverse.
<Vehicles with rear disc brake>
Brakes with the following specifications have been 
adopted for the rear.
•The 1-piston solid disc brake (S4-S35 <Vehicles 
with 16-inch wheel> or S6-S35 <Vehicles with 
18-inch wheel>) has been adopted.
*
•An audible wear indicator that informs the driver 
of application limit has been adopted onto the 
brake pads.
•The outer disc type brake disc which can be tight-
ened together with the wheel has been intro-
duced for better serviceability.
NOTE: *For the brake disc name, refer to FRONT 
BRAKE 
P.35A-8.
AC609282
AC609315
AC201769
Wear indicator Brake discPad Normal
AB
At wear limit
<16-inch disc brake (S6-S35)> <14-inch disc brake (S4-S35)> 
Page 209 of 241
CONSTRUCTION DESCRIPTION
BASIC BRAKE SYSTEM35A-10
BRAKE LINEM2350005000266
PROPORTIONING VALVE <Vehicles without ABS>
A proportioning valve is used to prevent early locking 
of the rear wheels, in order to provide improved sta
-
bility during braking.
AC609305
From master cylinder rear brake system
To rear brakeO-ring U-packing Sleeve
Guide Seal
Proportioning valveMaster cylinder
SpringPlateValve
AB 
Page 210 of 241
35B-1
GROUP 35B
FOUR-WHEEL 
ANTI-LOCK BRAKE 
SYSTEM (4ABS)
CONTENTS
GENERAL INFORMATION  . . . . . . . .35B-2
CONSTRUCTION DESCRIPTION . . .35B-6
SENSOR . . . . . . . . . . . . . . . . . . . . . . . . . . . 35B-6
ACTUATORS  . . . . . . . . . . . . . . . . . . . . . . . 35B-6
ABS-ECU. . . . . . . . . . . . . . . . . . . . . . . . . . . 35B-7