Page 431
Brake Pads
517-1
517 Brake Pads
General
517-1
Inspecting Brake Pads
517-1
Replacing Brake Pads
517-1
To replace front brake pads
(1985-1987 models)
517-2
To replace rear brake pads
(1985-1987 models)
To replace front brake pads
(1988 and later models)
To replace rear brake pads
(1988 and later models)
517-4
517-6
517-8
GENERAL
Since the disc brake assemblies and the parking brake are
self-adjusting it is not possible to judge the condition of the
brake pads from brake pedal travel or from the parking brake
lever. Pads should be inspected during regular service or
when any abnormal brake noise is noticed. The brake discs
should also be inspected during pad replacement as described in 516 Brake Discs.
INSPECTING BRAKE PADS
Inspection of the brake pads can be done after removing
the road wheel. The pads are made up of friction material and
are designed to wear away. Pad thickness is measured by
how much friction material is left. See Fig. 1.
WARNING
• Do not reuse any self-locking nuts or bolts. These fasteners
are designed to be used only once and should be replaced
anytime they are loosened or removed.
• Friction materials in the brake pads may contain asbestos fibers. Avoid breathing any asbestos fibers or dust. Always use
a respirator. Do not create dust by grinding or sanding, or by
cleaning the pads or disc with compressed air.
Fig. 1. Disc brake pads as viewed through opening in caliper
(road wheel removed). Minimum brake pad thickness
shown by dimension A.
Brake Pad Lining
NOTE
The front brake pads will usually wear out before the rear pads
owing to the fact that the front brakes do most of the stopping.
Always replace brake pads in complete sets. If the old pads
are to be reinstalled, make sure they are refitted in their originallocations. Inspect other parts such as springs, shims, hoses, and cables and replace as necessary.
Model
Minimum thickness
(dimension A)
1985 to 1987 models
1.0 mm (0.04 in.)
1988 and later models
4.0 mm (0.16 in.)
REPLACING BRAKE PADS
The brake pads can be easily replaced without disconnecting the flexible brake hose or the handbrake cable. This eliminates the need to bleed the brake system. In some cases,
special tools may be required to replace the pads. Read the
procedures completely before starting the job.
REPLACING BRAKE PADS
Page 432
517-2
Brake Pads
CAUTION
Different brake pads are used on different models. In addition,
some models require different inner and outer front brake
pads. Check with an authorized Saab dealer for the latest in
parts infonnation.
To replace front brake pads (1985-1987
models)
Fig. 2 shows the front brake assembly used on 1985
through 1987 models. Owing to the self-adjusting caliper assemblies, the caliper piston ratchets out as the brake pads are
used up. In order to fit the thicker new pads to the caliper, the
piston needs to be screwed back into the caliper housing and
this requires a special tool. See Fig. 3.
1
89007
Fig. 3. Special brake piston wrench (Saab tool no, 8996043) needed for pad replacement,
WARNING
Make sure the car is well supported with jackstands. Never
use just a jack to support a car.
2. Release the parking brake. Remove any rust and debris hom the brake disc.
7
3. Working at the caliper, push the parking brake lever towards the sliding yoke and unhook the parking brake
cable from the lever.
CAUTION
The parking brake lever must operate correctly. If the lever
sticks, the pads will not fully release from the brake disc. This
can lead to premature brake pad wear or even brake system
failure due to the constant heat.
NOTE
Check the operation of the parking brake lever by pushing it
fully towards the yoke and then releasing it. The retum spring
should cause the lever to snap back and contact the yoke. If
the parking brake lever does not fully release, the lever is
sticking in the caliper or the lever return spring is damaged. If
the lever cannot be made to move freely, the caliper must be
replaced as described under 523 Brake Calipers.
9
1. Sliding yoke
2. Indirect piston
3. Direct piston
4.
5.
6.
7.
Parking brake lever
Inner brake pad
Outer brake pad
Piston housing
a.
9.
10.
11.
12.
13.
89006-54304
U-c1ip
Damper (anti-rattle clip)
Anti-rattle spring
Parking brake lever return
spring
U-clip retaining pin
Bleeder
Fig. 2. Front brake assembly used on 1985 through 1987 models,
1. Raise the car and support it with jackstands. Remove
the front wheels.
REPLACING BRAKE PADS
4. Reconnect the parking brake cable to the lever. Check
that the parking brake cables are correctly adjusted by
checking for a small gap between the parking brake lever and yoke. Measure the gap as shown in Fig. 4. If
the clearance is incorrect, adjust the parking brake cables as described in 551 Parking Brake.
5. Remove the small retaining pin at the bottom of the Uclip, then pull the U-c1ip from the caliper. If necessary,
gently pry the U-clip out evenly using a large screwdriver.
Page 433
Brake Pads
517-3
CAUTION
Do not step on the brake pedal or apply the parking brake with
the brake pads removed. The piston will be forced out of the
caliper making it impossible to reinstall the pads without removing the caliper.
7. Clean the caliper assembly using brake cleaner and a
small wire brush. Be careful not to damage rubber
seals with the wire brush. Check that the yoke slides
freely in its groove in the caliper.
8. Lubricate the sliding surfaces between the caliper and
yoke using Gleitmo 540 lubricant, which is available
from an authorized Saab dealer. See Fig. 6.
Sliding yoke
Fig. 4. Parking brake lever gap being measured. Cable must be connected to lever when making measurement.
Parking brake adjustment
parking brake lever to
caliper clearance
O.S±O.1 mm (O.019±O.003 in.)
NOTE
Observe the position of the damper (anti-rattle clip) behind the
U-clip. During installation, the damper should be reinstalled in
the same position.
6. Remove the inner and outer pads from the caliper. The
pads can be removed from the caliper by grabbing the
pad using large pliers. As an alternative, a special
brake pad puller is available to help remove the pads.
See Fig. 5.
89012-S7080
Ag.6. Sliding surfaces of yoke to be lubricated using special grease
(Gleitmo 540).
9. Using the special brake piston wrench, engage the pins
of the wrench in the piston face and rotate the piston
clockwise. See Fig. 7. Remove the wrench and push
the piston into the caliper. If necessary, gently pry the
piston in using a screwdriver. Repeat the process until
the pads can be fitted.
CAUTION
Do not thread the piston in beyond the face of the caliper. See
Fig. 8. The piston seal and dust cover can be damaged. If the
piston is threaded all the way in and there still is not enough
clearance to install the pads, install the wrench to the piston
and carefully slide the yoke away from the caliper. Continue to
thread the piston in until the pads can be fitted.
Fig. 5.
Brake pads being removed from caliper. Special brake
pad puller (Saab tool no. 8995771) shown.
REPLACING BRAKE PADS
Page 434
517-4
Brake Pads
NOTE
NOTE
The piston can only be rotated a small amount at one time
with the wrench. After rotating the piston about 1/4 tum, remove the wrench and push the piston in.
Saab recommends thai the U-c1ips and dampers (anti-rattle
clips) be replaced whenever replacing brake pads. The Uclips are pre-bent to help prevent brake noise (clunking noise
when backing up). During nonnal use, the bends in the U-c1ips
tend to straighten out and the damper spring tension tends to
weaken.
11. Pull up the handbrake lever in the passenger compartment 7 notches (clicks). Start the engine and gently
pump the brake pedal several times. Release the lever
and then raise it 9 to 10 notches. The parking brake
should now be fully applied.
NOTE
Pulling up the hand brake lever 7 notches blocks the self adjusting mechanism of the caliper and prevents over adjustment. If the caliper is over adjusted, the brake pads will drag.
Fig. 7. Special wrench (Saab part no, 8996043) used to screw calIper piston In, Rotate piston clockwise only.
12. Install the road wheels and lower the car. Check the
brake fluid level and top up as necessary.
NOTE
Pushing the caliper piston in may cause brake fluid to overflow the master cylinder reservoir. To prevent this, use a
clean syringe or some equivalent to remove some fluid from
the reservoi r.
WARNING
New brake pads require some break-in. Allow for slightly longer stopping distances for the first 100 to 150 miles of city driving, and avoid hard stops.
Tightening torque
• wheel to wheel hub
(lug nuts)
90 to 110 Nm (66 to 88 ft-Ib)
To replace rear brake pads (1985-1987 models)
Fig. 9 shows the rear brake assembly on 1985 through
1987 models.
1. Raise the car and support it with jackstands. Remove
the rear wheels.
Fig. 8.
Piston shown flush to face of caliper (arrow). Piston must
• not be threaded beyond this point. If necessary, carefully
slide yoke away from caliper to rotate piston in further.
WARNING
Make sure the car is well supported with jackstands. Never
use just a jack to support a car.
10. Install the new brake pads, damper and U-clip. Install a
new retaining pin in the U-c1ip.
REPL4CING BRAKE PADS
2. Using a 2.5 mm drift, tap out the brake pad retaining
pins. See Fig. 10.
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Brake Pads
1
517-5
NOTE
• The brake pad shims are located on the rearof the pads. Label the shims during removal, as they are different between
the left and right wheels.
• The pads can be removed from the caliper by grabbing them
with a large pliers. As an altemative, a special brake pad puller
is available to help remove the pads. See Fig. 11.
1. Caliper housing
2. Brake pads
3. Damper (anti-rattle clip)
4. Brake pad retaining pins
5. Bleeder
Fig. 11. Brake pads being removed from caliper. Special brake
pad puller (Saab tool no. 89 95 771) shown.
Fig. 9.
Rear brake assembly used on 1985 through 1987 models.
CAUTION
Do not step on the brake pedal with the brake pads removed.
The piston will be forced out of the caliper.
4. Clean and inspect the caliper assembly, the pad retaining pins, and the shims using brake cleaner and a small
wire brush. Replace any worn components. Be careful
not to damage rubber seals with the wire brush. Inspect
the piston rubber dust cover and replace if necessary.
5. Using a screwdriver, gently push the piston back into
the caliper. Install the new brake pads with the shims.
CAUTION
Fig. 10. Brake pad retaining pins being tapped out of caliper.
Push the piston in just far enough to install the new brake
pads. Pushing the piston in too far may damage the piston
seals.
NOTE
Observe the position of the damper (anti-rattle clip) behind the
retaining pins. During installation, the damper should be reinstalled in the same position.
3. Remove the inner and outer pads together with pad
shims.
NOTE
Pushing the caliper piston in may cause brake fluid to overflow
the master cylinder reservoir. To prevent this, use a clean syringe or some equivalent to first remove some fluid from the
reservoir.
REPLACING BRAKE PADS
Page 436
517-6
Brake Pads
6. Install the damper (anti-rattle clip) and the pad retaining
pins. Tap the retaining pins in using a drift until they are
fully seated.
1. Raise the car and support it with jackstands. Remove
the front wheels.
7. Install the road wheels and lower the car. Gently pump
the brake pedal several times to seat the pads. Check
the brake fluid level and top up as necessary.
WARNING
Make sure the car is well supported with jackstands. Never
use just a jack to support a car.
WARNING
2. Working through the opening in the caliper, press the
brake piston back into the caliper housing using large
pliers. See Fig. 13.
New brake pads require some break-in. Allow for slightly longer stopping distances for the first 100 to 150 miles of city driving, and avoid hard stops.
3. While holding the lower guide pin stationary, remove
the brake caliper mounting bolt from the end of the
guide pin. See Fig. 14.
Tightening torque
• wheel to wheel hub
(lug nuts)
4. Swing the caliper up out of the way and remove the
brake pads. See Fig. 15.
90 to 110 Nm (66 to 88 ft-Ib)
CAUTION
To replace front brake pads (1988 and later
models)
Do not step on the brake pedal with the brake pads removed.
The piston will be forced out of the caliper damaging the seals.
Fig. 12 shows the front brake assembly used on 1988 and
later models.
1
11
1.
2.
3.
4.
5.
6.
Brake piston
Piston seal
Dust boot
Caliper housing
Brake pads
Guide pin boot
7. Guide pin
8. Caliper mounting bolt
(always replace)
9. Bleeder
10. Dust cap
11. Brake pad carrier
Fig. 12. Exploded view of front brake assembly (1988 and later
models).
REPLACING BRAKE PADS
Page 437
Brake Pads
517-7
NOTE
To prevent the piston from creeping out of the caliper, place a
strong rubber band around the piston and caliper to hold the
piston in.
5. Clean and inspect the caliper assembly, the guide pin,
and the pad carrier using brake cleaner and a small
wire brush. Replace any worn parts. Be careful not to
damage rubber seals with the wire brush. Inspect the
rubber dust covers for the piston and the guide pins.
Replace if necessary. Lightly lubricate the guide pins.
Fig. 13. Piston being pressed into caliper housing.
6. Using large pliers and a protective cloth covering the
piston, press the piston back into the caliper just
enough to install the new pads.
7. Install the new pads into the pad carrier and pivot the
caliper down into position. If necessary, push the lower
guide pin in as the caliper is lowered into position.
8. Install a new caliper mounting bolt in the lower guide
pin and tighten it while holding the guide pin stationary.
WARNING
Do not reuse the caliper self-locking mounting bolts. These
are designed to be used only once and should be always be
replaced.
Tightening torque
Fig. 14. Caliper mounting bolt being removed from lower guide
pin. Open-end wrench (arrow) being used to hold gUide
pin stationary.
• caliper mounting bolt
to guide pin
30 to 35 Nm (22 to 26 ft-Ib)
9. Install the road wheels and lower the car. Gently pump
the brake pedal several times to seat the pads. Check
the brake fl uid level and top up as necessary.
Tightening torque
• wheel lug bolts
105 to 125 Nm (77 to 92 ft-Ib)
WARNING
New brake pads require some break-in. Allow for slightly longer stopping distances for the first 100 to 150 miles of city driving, and avoid hard stops.
Fig. 15. Caliper (A) pivoted up to remove brake pads. Arrows
show brake pads.
REPLACING BRAKE PADS
Page 438
517-8
Brake Pads
To replace rear brake pads (1988 and later
models)
Fig. 16 shows the rear brake assembly used on 1988 and
later models.
1. Raise the car and support it with jackstands. Remove
the rear wheels.
WARNING
Make sure the car is well supported with jackstands. Never
use just a jack to support a car.
2. Disconnect the parking brake cable from the lever at
the caliper. See Fig. 17.
Fig. 17. Parking brake cable being disconnected from caliper.
3. Remove the plug covering the piston adjusting screw.
See Fig. 18.
5. Remove the dust caps from the guide pins then unscrew the upper and lower guide pins using a 7 mm internal-hex head wrench. See Fig. 20.
4. Loosen the piston adjusting screw using a 4 mm internal-hex head wrench until the piston moves against its
stop. See Fig. 19.
1.
2.
3.
4.
Guide pin plug
Boot
Guide pin (1 of 2 shown)
Bleeder
5.
6.
7.
8.
Dust cap
Piston seal
Piston seal
Dust boot
Fig. 16. Exploded view of rear brake assembly used on 1988 and later
models.
REPLACING BRAKE PADS
6. Remove the pad retaining clip. See Fig. 21.
9.
10.
11.
12.
Brake pads
Brake pad carrier
Pad retaining clip
Brake caliper
13. Parking brake lever
14. Piston adjusting screw
15. Plug for piston adjusting
screw
Page 439
Brake Pads
Fig. 18. Piston adjusting screw plug being removed using
517-9
Fig. 21. Pad retaining clip being removed,
wrench (arrow),
7. Remove the caliper from the pad carrier. Remove the
brake pads from the carrier. See Fig. 22.
Fig. 19. Internal-hex head wrench (arrow) to loosen piston ad
justing screw,
Fig. 22. Caliper being removed from pad carrier, Brake pad with
spring clip (arrow) is on piston side of caliper,
CAUTION
Do not step on the brake pedal with the brake pads removed,
The piston will be forced out of the caliper,
NOTE
To prevent the piston from creeping out of the caliper, place a
strong rubber band around the piston and caliper to hold the
piston in,
Fig. 20. Lower guide pin being removed from caliper, Upper
guide pin shown at arrow,
8. Clean and inspect the caliper assembly, the guide pins,
and the pad carrier using brake cleaner and a small
wire brush. Replace any worn parts. Inspect the rubber
dust covers for the piston and the guide pins. Replace
if necessary.
REPLACING BRAKE PADS
Page 440
517-10
Brake Pads
CAUTION
Be careful not to damage rubber seals with the wire brush.
9. Using large pliers and a protective cloth overthe piston,
press the piston back into the caliper.
10. Install the new pads in the pad carrier then install the
caliper.
11. Install and tighten the guide pins then install the guide
pin dust caps.
NOTE
No lubrication is specified for the rear guide pins.
13. Turn the piston adjusting screw all the way. See Fig. 19
above. Then back the screw out 1/4 to 1/2 turn. Check
that the brake disc rotates freely.
14. Install the plug for the adjusting screw then reconnect
the parking brake cable.
15. Check the adjustment of the parking brake cable as described in 551 Parking Brake. Adjust the cable if necessary.
16. Install the road wheels and lower the car. Gently pump
the brake pedal several times to seat the pads. Check
the brake fluid level and top up as necessary.
WARNING
New brake pads require some break-in. Allow for slightly longer stopping distances for the first 100 to 150 miles of city driving, and avoid hard stops.
Tightening torque
• rear caliper to pad carrier
(guide pins)
25 to 30 Nm (18 to 22 ft-Ib)
12. Install the pad retaining clip as shown above in Fig. 21.
REPLACING BRAKE PADS
Tightening torque
• wheel to wheel hub
(lug bolts)
105 to 125 Nm (77 to 92 ft-Ib)