900 L4-1985cc 2.0L DOHC (1986)
Brake Caliper: Customer Interest
Front Brakes - Dragging
FILE IN S.I. Man VOL. I
SEC. A-5 PG. 30
Service Information
SUBJECT:
FRONT BRAKE DRAG: NEW CARS, CARS ISSUE: 10/86-895
WITH NEW FRONT CALIPERS
SUPERSEDES: 05/86-847
APPLICATION: SAAB 900 MODELS
A complaint of brake pad smell or smoking (i.e. brake drag) results from prolonged running contact between the pads and the disc. The needed clearance
may not be maintained if full brake pedal return is obstructed or if the initial hand brake adjustment is too tight to allow for the normal tendency of new
brake pad friction material to swell during the bedding-in process. Other symptoms may include the car slows down by itself or the hand brake lever
travel is extremely short.
Assuming that the initial hand brake clearance was sufficient (checked at PDI), a dragging complaint may be due to the front brake self-adjuster
mechanism being too sensitive for the driver's braking habits or driving conditions. Frequent brake applications with relatively high force resulting in
little or no pad wear can be such a condition.
The self-adjuster manufacturing tolerance has been altered slightly in the current production to eliminate acceptance of units which may be too sensitive
in stop and go driving. To correct brake drag complaints, selected front caliper assemblies with low adjuster sensitivity are now available under special
part numbers. Such calipers are also now available for cars with vented discs. The calipers listed below must only be replaced in pairs and should be
ordered only in the case of a brake drag complaint. Use the standard part numbers otherwise.
91-02-807
LH Caliper, for solid discs
91-02-815
RH Caliper, for solid discs
91-03-458 (new) LH Caliper, for vented discs 91-03-466 (new) RH Caliper, for vented discs
When correcting a brake drag complaint, the outer brake pads need not and should not be replaced unless damaged by heat. However, it is advisable to
install the new Textar inner pads, 91-02-708, whenever dealing with this complaint. See also S.I. 07/86-861 and S.I. 07/86-862.
Caliper Replacement Procedure
1.
Remove the front brake pads and disconnect the hand brake cable from the front brake housing. Remove the brake lines and cap off to prevent
excessive fluid loss. Remove the bolts which attach the caliper sets to the steering knuckle. Remove both calipers and replace with the special
replacement calipers listed above.
2.
Install the original outer DM-121 pads if undamaged by excessive heat and if the remaining pad thickness exceeds 4 mm. Install new Textar T474
inner pads. Brake pads must not have any rubber material (sound deadening) applied to the back of the pads or shims. These can contribute to a
drag complaint.
3.
Check the hand brake cable clearance 0.019 +/- .003" 0.5 +/- 0.1 mm) at the caliper levers and adjust if necessary.
4.
Top up the brake fluid check for leaks and bleed the system (DOT 4 only).
