suspension MITSUBISHI ECLIPSE 1990 Service Manual

o-4GENERAL - Technical Features
BASIC CONSTRUCTION
The 4WD vehicles are equipped with
2.OL DOHC
16-valve turbocharged engine and incorporate new
technologies such as full time 4WD of center
differential type with viscous coupling differential
limiting for excellent running stability and excellent
Steering
l Light weight and compact rack and pinion
type for high steering response
l Tilt steering mechanism to give optimum
driving position
\driving across bad roads, and $-wheel independent
suspension for comfortable riding.
Adopted on
2WD vehicles are 2.OL DOHC 16-valveengine, MacPherson strut type front suspension
and torsion axle
typ.e 3-link rear suspension.
Rear suspension
l Self-aligning double wishbone type suspen-
sion for comfortable ride
(4WD)l Torsion axle type 3 link suspension for
outstanding driving stability
(2WD)l Negative chamber for outstanding steer-
ability during high speed driving
0 Anti-lift geometry for high stability duringbraking
lIntegral torsional bar type axle beam for
optimum roll stiffness (2WD)
\Front propeller shaft (3-piece
4-joint type)
lRobro joint to absorb lengthwise and angular
change and prevent transmission of vibrations.
(4WD)
IFront suspension
The front suspension of McPherson strut type
independent suspension system
l Under steer geometry for outstanding steering
stability
l Negative offset geometry for outstanding
stabil-ity at braking
0 Offset coil springs for comfortable ride
Brakes
l Cross piping dual type proportioning valvethat keeps balanced braking power even at
failure of the hydraulic system.
l Four wheel disc brake system for high
braking power.

o-14GENERAL - General Data and Specifications
tiems
Chassis
TireFront suspension
Type
Rear suspensionType
Brake
TypeFront
RearSteering
Gear type
Gear ratio
Fuel tankCapacity liters (gals.)
P205/55HR16 or
205l55VR 16Independent strut
3-Link
Torsion axleDisc
Disc
Rack and pinion
m
60 (16)
P205/55VR 16 or205155VR16Independent strut
3-Link
Torsion axleDisc
Disc
Rack and pinion
00
60 (16)
P205155VR16 or205155VR16Independent strut
Double wishbone
Disc
Disc
Rack and pinion
co
60 (16)ENGINE SPECIFICATIONS
Items
TypeNumber of cylinders
Boremm (in.)Stroke
mm (in.)Piston displacement
Compression ratio
Firing order
cm3 (cu.in.)
4G63 (2.OL) Non-Turbo1 4663 (2.OL) Turbo
In-line DOHC~ In-line DOHC
4‘4
85.0 (3.35)
85.0 (3.35)
88.0 (3.46)88.0 (3.46)
1,997 (122)
1,997 (122)
9.0
7.8l-3-4-2l-3-4-2
TRANSAXLE SPECIFICATIONS
Items
Type
Gear ratioTransfer ratio
gearFinal drive ratio
gear
1st
2nd
3rd4th5th
ReverseF5M22F5M33
W5M33F4A22
5-speed M/T5-speed M/T&speed ArF4-speed AiT
3.3633.038
3.0832.846
1.9471.8331.6841.581
1.2851.2171.1151 .ooo0.9390.8880.8330.686
0.756
0.7410.666
3.0833.166
’3.1662.176
-1.090
3.9413.4373.8663.562

it?
2-1
FRONT
SUSPENSION
no2&--
ANTI-DIVE GEOMETRY .................................... 5 LOWER AR M........................................................ 7

FRONT SUSPENSION - General Information2-3
SPECIFICATIONS
<2WD>terns
Suspension system
Camber
Caster
Toe-inmm (in.)
Coil springWire dia. x O.D.
x free lengthmm (in.)Coil spring identification color
Spring constantN/mm (IbsAn.)
Shock absorber
TypeMax. length
mm (in.)Min. length.
mm (in.)
Strokemm (in.)Damping force [at
0.3. m/set. (.984 ft./sec.)l
Expansion
N (Ibs.)Contraction
N (Ibs.)
Non-TurboTurbo
With a manualWith an automatic
With a manualtransaxletransaxletransaxle
McPherson strut with coil spring and compression rod type
5’
z!z 30’
2”24’ 31 30’
0
It 3 (0 * .12)
13.7x173.7x314 13.9x173.9x321.5
(.54 x 6.84 x 12.4)l.55 x 6.85 x 12.7)
Light blue x 1Light blue x 2
24 (134)24 (134)Hydraulic, cylindrical double-acting type
483
(19.02)330 (12.99)
153
(6.02)1,000
(220)300
(66)

FRONT SUSPENSION - General Information
c4WD>Items
Suspension system
CamberCaster
Toe-inmm (in.)
Coil springWire dia. x O.D. x free length
mm (in.)Coil spring identification color
Spring constantN/mm
(Ibs./in.)
Shock absorber
TypeMax. length
mm (in.)Min. length
mm (in.)
Strokemm (in.)Damping force [at 0.3
m/set. (.984 ft./set.)]Expansion
N (Ibs.)Contraction
N (Ibs.)Specifications
McPherson strut with coil spring and compression rod type
10’
+- 30’
2”18’ + 30’
0
zk 3 (0 f .l2)14.0 x 174.0
x 326.5 (.55 x 6.85 x 12.9)
Pink x 1
26 (146)
Hydraulic, cylindrical double-acting type
489 (19.25)
340 (13.39)
149 (5.87)
1,000 (220)
300 (66)

FRONT SUSPENSION - Anti-dive Geometry / Negative-offset Geometry2-5ANTI-DIVE GEOMETRY
RO2cAAAOrdinarily, when the brakes are applied, the load is moved
toward the front of the vehicle as the result of inertial force, and
this causes the phenomenon known as “nose dive”, in which
the front of the vehicle is caused to tilt forward and downward.
For this front suspension, however, the suspension link design
-which has a high
“anti-dive” effect- is such that the lower
arm is tilted forward in order to counteract the “nose dive”
phenomenon.
In other words, braking force
F is divided into force compo-
nents
F, and F2; of these, F1 acts in the direction that expands
the front spring, with an effect that reduces the “nose dive”
phenomenon.
NEGATIVE-OFFSET GEOMETRY
AOZDAAAFor negative-offset geometry. the king pin offset
angle is outside the center point of tire-to-ground
contact. Thus, for example, if a tire on the right side
is punctured during driving, or if the brakes are
applied while the left tires are on a slippery surface
(ice, etc.), the vehicle would be inclined to swerve to
the side (in this case the right side) of greater road
surface resistance to the tires, but, because of the
negative-offset geometry construction, a certain
force would be generated to cause rotation in
direction C, employing point A as the fulcrum point.
At the same time, there would be generated at the
tires on the opposite side a corresponding force to
cause rotation in direction D, also employing point A
as the fulcrum point, but, because that force is
Centreooint of strutPatigreater in direction
C (where road surface resistance
is greater), the tires themselves will tend to turn in
the left direction. As a result,. because
t.he tires
automatically countersteer in the left direction, even
though the force applied to the vehicle by the road
surface resistance is to the right, the system thus
functions to maintain the vehicle on a relatively
straight-ahead course.
NOTEThe king pin offset is the distance from the center
point of tire-to-ground contact when a line (ex-
tended to the road surface) is drawn to connect the
ball joint center point and the center point of the
strut upper installation part.
Point AIcy surface
12AO548
Ball jointLcentre point t
Directionof travel
Direction
of tire
4--
Direction ofmovement tendency>f;’*Jvehicle move-:’
”ment tendency,
12AOO30

----2-6
FRONT SUSPENSION - Offset Spring
OFFSET SPRINGBecause struts are installed at an angle, the road
surface reaction force
(RI) applied to the tyres tends
to act vertically upon the tyre centre, and that force
tries to bend the strut toward the inside of the
vehicle. When this happens, the force trying to bend
the strut toward the inside of the vetiicle acts upon
the strut bearing component as bending moment
reaction force
FL (because the upper part of the strut
is fixed in place), thus increasing the friction of the
bearing, and, as a result of the bending of the strut,
amplifying the moving resistance of the shock
absorber.Ro2EMA
Then, because the coil spring
is installed so that itscentre is greatly offset (toward the outside of the
vehicle) from the centre of the strut, the counterac-
tive force for the spring tends to become great
toward the outside of the vehicle, thus resulting in
the generation of bending force
FL opposite to the
bending of the strut, and thereby decreasing the
friction applied to the strut bearing. As a result, the
shock absorber’s internal movement friction is
reduced, thereby improving riding comfort as well
as the durability of components.
Spring counteractiveforce
RI : Road surface reaction forceR2: Strut axial-reaction forceR3: Strut bend direction reaction forceR4: Strut bending force (by spring offset)

FRONT SUSPENSION- Lower Arm / Stabilizer2-7
LOWER ARM
ROZGAAAThe lower arm is an A-type arm, and is connected,
via a rubber bushing, to the crossmember.
The rod bushing is optimum tuned, including the
spring constant of the arm bushing, to provideand “hard” characteristics relative to the left and
right, so that road surface impacts during travel are
alleviated, and also so that changes of alignment
caused by lateral forces are reduced, thus assuring
“soft” characteristics relative to the front and rear
excellent
I driving stability.
Arm bushing
,m
Rod bushing
STABILIZERROZHAABThe stabilizer mounting uses
*pillow balls. The
adoption of a stabilizer link with a pillow ball on each
end increases the link stiffness and ensures the
effective operation of the stabilizer bar even when asmall rolling motion occurs,
NOTE* Pillow ball: Ball joint not preloaded.
Pillow ballStabilizer bar
12AOOOS
4--

2-8FRONT SUSPENSION - Front Axle
FRONT AXLEROPKAAAThe drive shaft is of the Bit-field joint
(B.J.)-tripodjoint
(T.J.) type. This type features high power
transmission efficiency and low vibration and noise.The knuckle has the wheel bearing assembled
a@the hub press-fitted. The drive shaft and hub are
spline-coupled.
T.J.: Tripod Joint
B.J.: Birfield Joint
Hub
DRIVE SHAFT
B.J.-T.J. constant velocity joint combination main-
tains speed completely even when flexed, can
withstand heavy loads and shock and offer high
power transmission efficiency. Their special fea-
tures are outlined below.
B.J.T.J.l Axially
slidablel Smaller sliding resistance
0 Large operating angle
l Compact size and decreased space
require-
me&Taking these characteristics into account, B.J. is
adopted on the wheel side of the shaft, as it can
make large deflections when the tire is steered and
T.J. is adopted on the transmission side, as it can
slide
axiallv to absorb the chanae in the distance
between joints caused by
motionWof the suspension.
B.J.T.J.
llA0123

FRONT SUSPENSION - Front Axle2-9
HUB AND KNUCKLEThe construction of the hub and knuckle consists of
The wheel bearing is the double-row,
angular-the wheel bearing assembled to the knuckle and the
contact ball bearing type to withstand the lateral
hub pressed in; the drive shaft and hub are coupled
(thrust) load. The installation of the brake disc and
by
&rations.hub are the outer disc configuration, thus improving
serviceability and also reducing rotation unbalance.
Wheel bearing
Oil seal
HubDust shi&d
II I
IllA0053
Oil seal/HubBraie
disc
11 A0295
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