Flushing/Bleeding the Saab 9000 Braking System
The Saab 9000 braking system, like most others, is a hydraulic system requiring bleeding after any part of the system has been dismantled and also flushing with new fluid at specified intervals (I do it when I buy a car and every two years thereafter). Most recently, I performed this procedure after replacing all the brake hoses on my '96 Aero with stainless steel braided hoses.
My main reference while writing this article was the Haynes 9000 workshop manual.
A note about brake fluid standards:
DOT 5.1 brake fluid is a low-viscosity, high-temperature fluid compatible with DOT 4 and DOT 3. Its low viscosity makes it ideally suited for ABS systems, where it helps the system modulate the braking pressure more easily. Its higher wet and dry boiling points should make it more resistant to brake fade under heavy use. I have had no problems with the braking system since installing this fluid.
DOT 5 and DOT 5.1 are very different standards, confusingly named by the US Department Of Transport. Of the two, only DOT 5.1 is compatible with DOT 4. Do not use DOT 5 fluid unless you have a good reason and know how to purge the system of all DOT 4 fluid beforehand (this usually requires complete dismantling of the braking system and cleaning of the individual components with a suitable solvent). Mixing DOT 5 fluid with any traces of DOT 4 will form precipitants that will clog the braking system.
If in doubt, use DOT 4 brake fluid. It will be fine for the driving conditions encountered by most 9000s.
Unless you come across some seized bleed screws (I haven't yet on a 9000), the procedure should take around 10-15 minutes per caliper.
As usual, double this for the first caliper if you haven't done it before.
I assume some basic tools, such as a jack, axle stands, socket set, etc. However I do not assume you will already have all the necessary metric socket and spanner sizes, especially if you are in the USA. Here is a list so you can make sure you have all the necessary sizes before you start.
Flushing the system is almost the same as bleeding all four calipers, except that you bleed off more fluid. On a car with manual transmission, DON'T press the clutch pedal while the fluid in the reservoir is low. The clutch shares the same reservoir and fluid and doing this may introduce air into the clutch. After flushing the braking system, the clutch should really be flushed as well to prevent contamination of the new brake fluid. I haven't done this without a pressure bleeder, so I won't describe it here.
The bleed screws are 9mm on my '96 (ABS with ATE calipers all round). I'm told the Girling front calipers (non-ABS and early ABS non-turbo) also have 9mm bleed screws.
BLEEDING THE FRONT BRAKES (AND REAR BRAKES ON NON-ABS SYSTEMS)
Note that on non-ABS systems, the calipers may be bled in any order. On ABS systems, the front brakes must be bled first. The manual procedure is described here, which requires an assistant. I use a pressure bleeder, which makes life a lot easier.
N.B. I found that my pressure bleeder (which is fed from a spare tyre and is rated to 20 PSI) could not bleed the rear brakes on my '96 ABS braking system. I'm told that more pressure would have done the trick. I simply followed the manual procedure below instead.
|saab9000.com is an enthusiast's web site
and is not in any way affiliated with Saab Automobile. A big "thank
you" to Saab for producing the 9000.
All information is presented in good faith. However, I am not a trained mechanic, just an enthusiast.Therefore, it is your responsibility to ensure that you are competent to carry out any procedures presented here and that they are correct. No responsibility can be accepted for any inaccuracies or consequential loss, injury or damage.
|Copyright © 2001-2013 Bill Jones|