Page 681
SHOCK ABSORBERS
GENERAL
Defective shock absorbers should be exchanged. This is
extremely important, as the shock absorbers contribute
largely to the good roadholding and steering characteristics of the car.
Shock absorbers on the same axle should be exchanged in
pairs.
As from model 1976, pneumatic shock absorbers will be
available as an alternative.
As from the middle of 1976 model production Saab 99
EMS and TURBO are fitted with special rally-type pneumatic shock absorbers, front and rear.
er is installed, any air present in it must be expelled. To
bleed the shock absorber, hold it upright in the same position as when installed, pump it up and down for a few
full strokes, and then install it in the car. If the shock absorber is laid flat, more air can enter through the valve
system.
Fit rubber bushings and washers. Note the positions of
the washers as illustrated opposite. The nuts of the front
shock absorbers should be tightened hard, while those on
the back shock absorbers should be tightened enough to
provide suitable tension against the rubber bushings.
REAR SHOCK ABSORBERS, SAAB 99 EMS
Owing to the high compression of rally-type shock absorbers, the procedure for changing them is slightly more
involved than that for hydraulic shock absorbers.
REMOVAL
1. Jack up the car and take off the wheel.
2. Unscrew the shock absorber, saving the washers and
rubber parts.
Removal and installation
1. Raise and block up the car at the rear jacking point.
2. Place an additional trestle under the rear axle to prevent it dropping and stretching the brake lines.
3. Insert a jack at the rear of the spring link.
4. Remove the shock-absorber nuts.
5. Remove the bolts in the spring-link mounting on the
rear axle.
6. By means of the jack, lower the spring link so that the
shockabsorber can be removed.
54382
SHOCK ABSORBERS
INSTALLATION
Inspect the rubber parts and exchange any that are defective. Use only original Saab rubber parts and washers
at the upper and lower attachment points when installing
shock absorbers; poorly fitting substitutes can cause body
noise when the car is on the road. Before a shock absorb-
REMOVAL OF PNEUMATIC SHOCK ABSORBER, REAR
Fitting is carried out in the reverse order.
SAAB
761-1
Page 682
CHECKING OF SHOCK ABSORBERS INSTALLED IN
CAR
Check the condition of the shock absorbers as follows:
1. Check for leakage of oil from the shock absorbers.
2. Check for external damage, extensive corrosion or
bends in the plungers.
3. Check that the nuts are tight.
4. Check the condition of the rubber bushings.
5. Test the functioning of the shock absorbers by rocking the car or in conjunction with test driving.
REGULATIONS FOR SCRAPPING PNEUMATIC
SHOCK ABSORBERS
Pneumatic shock absorbers contain gas under a pressure
of 30-40 bars which can cause personal injury if not handled properly.
In order to avoid the risk of personal injury pneumatic
shock absorbers should emptied of gas prior to being scrapped. This is effected by drilling a 0 2 mm approx. hole in
the pressure chamber 10-15 mm from the edge. See illustration below.
....
0
....
LC)
I
....
0
....
LC)
I
S 7312
Pneumatic shock absorber
with rubber bellows, gas
chamber at top
761-2
Drill a 0 2 mm hole
10-15 mm from the edge.
SMB
Pneumatic shock absorber
with plas~ic or steel casing,
gas chamber at bottom.
Drill a 0 2 mm hole
10-15 mm from the edge.
Page 683
WHEELS
Aluminium wheels
FITTING OF WHEELS
From the viewpoints of comfort and safety, it is important that the wheels be fitted correctly. The following
procedure is recommended.
Steel wheels
1. Check the taper and threads of the nuts. Nuts which
seize or on which the taper is worn should be replaced.
1. Check the nuts and threads for damage.
2. Mount the wheel on the hub and tighten the nuts so
that the wheel locates correctly.
If the wheel has been removed and fitted on frequent
occasions, the seating between the nut and the wheel
may be worn, making centring difficult. Particular attention should be given to this in conjunction with
complaints concerning vibration. The following procedure is recommended in such cases.
Guide the wheel onto the hub by means of two nuts
with cones (89 19 656) located at 180° from each
other. Tighten the wheel with the conventional nuts
in the two remaining holes and then change the cone
nuts.
As from 1978 model the hubs are used to centralize
the wheels. The surfaces coming into contact with
the centre of the wheel should be coated with rustpreventive oil.
3. Tighten the nuts to a torque of 88-108 Nm (65-80
ft.lb., 9-11 kpm).
NOTE
Pneumatic nut tighteners must not be used for final
tightening of the 11uts.
S 5992
ADJUSTING AND REPAIRING WHEELS
Wheels may be damaged in collisions or if the car runs off
the road or is driven on underinflated tires. As the tubeless tires seal direct against the wheel rims, air will leak
out if the rim is deformed or otherwise damaged. If a leak
occurs due to rim deformation, the tire should be taken
off so that the wheel can be inspected and adjusted if necessary. If the rim is rusty at the bead seating, the rust
must be removed; this can suitably be dom~ with a steel
brush or a pad of steel wool. If rust has pitted the rim, a
file should be used. Any minor pits remaining after adjustment should be coated with thick rubber solution; the
tire is then coated in the same way and mounted on the
wheel before the solution dries.
S 5993
NUT WITH WORN TAPER
NOTE
Check before mounting the tire that the rim is not
out-of-round or out-of-true.
2. Mount the wheel on the hub and tighten the nuts so
that the wheel locates correctly.
3. Tighten the nuts to a torque of 88-108 Nm (65-80
ft.lb.,.9-11 kpm).
On a correctly journaled rotating rim, the difference between the highest and lowest point measured at A (see
illustration) must not exceed 0.047"/1.2 mm (Saab 99
EMS: 0.032"/0.8 mm). The side throw B (see illustration)
should be measured in the same way and must not exceed 0.047"/1.2 mm (Saab 99 EMS: 0.032"/0.8 mm).
When these measurements are made, the rim should be
mounted in the usual way, either on a wheel hub or in a
special apparatus, so that the rim can be rotated.
NOTE
Pneumatic nut tighteners may only be used in combination with a torque wrench. Nuts which have been
overtightened can damage the wheel and make it impossible for the motorist to remove the nuts in the
event of a puncture.
SMB
771-1
Page 684
FITTING WEIGHTS TO ALUMINIUM
Since the wheel-balancing weights are placed about 1/2
in inside the wheel in the case of aluminium wheels, allowance must be made for this in the case of wheel-balancing
machines set to the wheel width. Accordingly, the machine
should be set for 4 1/2 in in the case of 5 1/2 in wheels.
In the case of certain types of balancing machines, the
emblem at the centre of the wheel must first be removed.
Use special drift 8996167 to remove and refit metal emblems.
S 1761
MEASUREMENT POINTS ON THE WHEEL RIM
Aluminium wheels
For the balancing of aluminium wheels, special weights
that are glued to the wheel must be used. Ensure that the
surface has been thoroughly cleaned and dried before
glueing.
REMOVING THE METAL EMBLEM
FITTING WEIGHTS TO ALUMINIUM
771-2
WHEELS
WHEELS
--.L
Page 685
6. Road surface. Dry roads offering a good grip for the
tires cause a great deal of wear.
7. Manner of driving. The temperament of the driver may
weigh more heavily than any other factor. If the acceleration and braking resources of the car are regularly
utilized to the limit, this will quickly wear down the
tires.
A statically balanced wheel should be able to come to
rest in any position when suspended and free to rotate.
A dynamically balanced wheel should rotate in a plane
perpendicular to the axis of rotation, i.e. it should have
no tendency to skew during rotation.
The balancing operation should not be performed on new
wheels, but only after some 600-900 miles ( 1,000-1,500
km) motoring; this is to give the tire time to "shake down"
on the rim.
Wheels need rebalancing after long mileage because tire
wear alters the distribution of weight.
FITTING THE EMBLEM
Tool 89 96 167
NOTE
When a wheel spinner is used, the speedometer reading must not exceed 40 mph (70 km/h).
TIRE MAINTENANCE
The working life of a tire depends very much on the care
it receives and the conditions under which it has to work.
Some of the factors affecting tire wear are listed below.
1. Inflation pressure. It is important to maintain the correct inflation pressure and to adjust the pressure according to load. For correct tire pressures, see under
Specifications, Group 0.
S 1762
TREAD CONTACT WITH ROADWAY
2. Wheel balancing is necessary to avoid vibration and
consequent wear. Wheels must be balanced both statically and dynamically.
3. Wheel alignment. Faulty alignment of the wheels can
cause heavy wear on the tires.
4. Speed. Tire mileage diminishes sharply with rising
speed, mainly due to the greater friction heat generated.
5. Engine power. Powerful engines give rapid acceleration
and high speed, which in turn demand powerful brakes.
This contributes to faster wear on the tires.
SAM!
771-3
Page 687
HUBS
FRONT WHEEL HUBS
The hub and brake disc constitute two separate cast components, held together by four screws, locked by means
of a locking plate. The front wheel hub is splined to the
outer drive shaft and is secured by a nut with a flange
which is upset in the locking groove in the axle.
The four wheel bolts are forcefitted in the hub.
1 2
3
4
5
6
S4379
FRONT WHEEL HUB
1. Lock nut
2. Washer
3. Hub
4. Outer drive shaft
5. Wheel bearings with seals
6. Outer drive shaft joint
SAAB
774-1
Page 688
WHEEL BEARINGS
Changingfront wheel bearings
In time wheel bearings may become so worn that they develop play. If the play measured at the wheel rim exceeds
0.08" (2 mm), the wheel bearing must be renewed. Under
no circumstances must wheel bearings be subjected to impact, as this may damage them.
When separating the inner universal joint, fit a cover in
the rubber bellows to stop the needle bearings tram falling out and to keep dirt out of the joint, and fit a cover
over the inner driver.
7. Pull out the drive shaft through the wheel housing,
remove the entire front axle assembly and clean it
thoroughly.
NOTE
Use only original bearings as listed in the
Spare Parts Catalogue.
The bearings cannot be taken apart.
Removal
1.
2.
3.
4.
Take off the hub cap and remove the lock nut.
Slacken the wheel nuts.
Block up the front of the car on trestles and remove
the wheel.
Turn the brake disc so that the recess in the edge of
the disc is in line with the brake pads. Loosen the
handbrake cable and remove the brake housing.
Hang up the brake housing to avoid damage to the
brake hose.
Remove the hub and brake disc from the axle using
puller 89 95 185 and four spacer screws 89 96 050
or with puller 89 96 084 (later design).
REMOVING THE FRONT AXLE ASSEMBLY
8.
Place the steering knuckle housing in a press and
press out the drive shaft.
REMOVING THE BRAKE DISC FROM THE HUB
Puller 8995185 and spacer screws 8996050 or as alternative
tool 8996084 Oater design)
'
REMOVING THE DRIVE SHAFT FROM THE HUB
5.
6.
774-2
Undo the large clamp round the rubber bellows of
the inner universal joint.
Remove the steering arm and upper ball joint using
tool 8995409. Undo the screws on the lower control arm bracket.
SA.ii&
9.
R~move t~e lock ~ing and press out the bearing
using a suitable drift. The bearing must not be taken apart.
Page 689
REMOVING THE CIRCLIP
RELEASING PRESSURE ON THE CIRCLIP BY PRESSING
THE TWO WASHERS TOGETHER
c. Open the circlip using circlip pliers and release
the pressure.
REMOVING THE BEARING
10.
Remove the intermediate drive shaft from the outer universal joint hub as follows:
a. Loosen the outer universal joint bellows and
move the bellows along the shaft.
b. Place the shafts in a press and press together the
two conical spring washers so that the circlip inside the hub can rotate in the groove.
OPENING THE CIRCLIP WITH CIRCLIP PLIERS
d. Pull the intermediate shaft out of the hub together with the spherical shaped washer, the two
coneshaped spring washers and the shaft locking
ring. The circlip on the hub remains in the groove.
774-3
Page 690
2.
Installation
Before beginning assembly, clean and inspect all axle components and exchange any worn or damaged parts for new
ones. Check the rubber bellows with special care.
1. Assemble the intermediate drive shaft to the outer
universal joint as follows:
a. Fit the axle locking ring, the two concave sides
facing inwards) and the spherical-shaped washer.
Push the shaft into the universal joint hub.
Press the front wheel bearing into the steering
knuckle housing using tool 8996068. Fit the
locking ring.
Before fitting, grease the bearing with "Molycote,
Paste G".
FITTING THE FRONT WHEEL BEARING
Drift 8996068
3.
Mount the outer drive shaft in the press and press
the knuckle housing and bearing on to it. Press on
the inner sealing ring.
DRIVE SHAFT WITH LOCK RING AND WASHERS
b. Place the unit in a press and press together the
conical spring washers so that the circlip inside
the hub clicks into the groove in the shaft. Pull
the shaft to check that it is held securely.
c. Pack the joint with grease and assemble the rubber bellows. The bellows clips are fitted with the
aid of tool 7844699.
54392
FITTING THE STEERING KNUCKLE HOUSING AND
BEARING TO THE OUTER DRIVE SHAFT
4.
FITTING THE OUTER BELLOWS CLAMP
Pliers 7844699
774-4
Sll\ftB
.L
Press the wheel hub and brake disc onto the drive
shaft splines and fit the conical washer and lock
nut. The nut is locked later.