NG 900/9-3 Rear Brake Pads
Rear brakes are a trouble spot on cars driven under harsh winter conditions and road salt. The rear brakes have fixed calipers, with dual pistons and pads sliding on pins and held in place with a spring (clip). Calipers, brake lines, and handbrake parts often rust and seize, brake pads wear unevenly when caliper pistons stop working, or when pad backing plates start to bind inside the caliper due to rust and brake dust buildup.
Brake pads are accessible with the wheel off without removing the brake caliper. Parts needed when replacing the pads may include a kit with pins and springs and a packet of brake grease.
Pins and Springs
Pins are driven out using a punch. The spring will come loose after the first pin is removed. Pins and springs can usually be cleaned and reused, but the pin has to be smooth to allow the pad to slide along the pin. When they become corroded as shown on the left, they should be replaced with a new kit.
The Saab OEM springs are better fit and quality than the most popular aftermarket kit made by Scantech.
Pads can be removed using pliers or a pad removal tool. Minimum pad thickness is 5 mm, (not including the backing plate). The pads may stick on a ridge built up on the rotor due to wear, or because rust and brake dust collects inside the caliper, and may have to be pushed side-to-side before they come loose. The caliper cavity can be cleaned out with a wire brush once the pads are out.
The pistons have to be pushed into the caliper to make room for the new pads. According to the Haynes manual, the orientation of a cutout in the piston should be checked, and if necessary rotated toward the bottom, so moisture can drain out properly.
Apply some brake grease to the back of the pads and insert them into the caliper. Insert the top pin as far as it will go by hand, then tap it in the rest of the way using a hammer.
Hook the spring clip under the top pin, then insert the lower pin while pushing the spring down. Do not bend or force the spring. The lower pin should fit into a u-shaped hollow in the clip easily. Tap the lower pin in place. Apply dabs of brake grease to the pins where they meet the pad backing plates.
10 mm (new) 5 mm (minimum)
- 1/8-inch punch
- Pliers or pad extraction tool
- Wire brush
- Brake cleaner
- Brake grease
Saab EPC 5-0150
Haynes Ch 9, section 5
Brakes are larger on '97 and later models, and have different part numbers for pads, rotors, and the kit with pins and springs.