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Discussion Starter · #1 ·
I am sure that most Saabsceners are sensible people who change their brake fluid regularly, however, just in case, I'd like to bring the following to your attention.

Castrol, purveyors of quality brake fluid for generations, recently tested a number of cars in the car park of their office in Pangbourne (where you might think that people would be aware of the problem) with scary results. Here is a copy of their subsequent safety notice.

Quote starts..................................

The brake fluid check was available to Pangbourne staff for 2 days and involved testing the Vapour Lock Point of a brake fluid sample taken from the brake system reservoir.

36% of the Pangbourne “car park” took part in the test program

47% of cars tested had very poor condition brake fluid.
20% of cars tested had fluid that required immediate replacing

NB the fluid in the reservoir is normally in better condition than the fluid found at the road wheels.

Why change brake fluid?
Brake fluid is hygroscopic - it attracts and absorbs water. This is unavoidable, it is part of brake fluid’s chemistry and even though it is in a “closed” system, the attraction for water is so strong that it is still absorbed. When brake fluid absorbs water its boiling point is reduced. This deterioration continues and eventually the heat produced by friction between the brake lining materials and discs or drums will vaporise the fluid. Vapour, unlike liquid, is compressible, so pressing the brake pedal merely compresses vapour instead of operating the brakes. (This is known as the vapour lock point and it is slightly lower than the boiling point). This kind of brake failure can only be avoided by changing the brake fluid regularly.

When should brake fluid be changed?
Unlike engine oil which should be changed according to the distance driven, brake fluid deteriorates not with distance but with time. It continues to absorb water even when the vehicle is stationary. Most vehicle manufacturers recommend regular brake fluid changes on a time basis.

Many people are complacent about their brake fluid, assuming that it will always do the job.
I have seen many cases of serious injury and death through Brake Fluid Neglect.
Garages rarely have the equipment to check the fluid condition, settling only to look at hose condition and reservoir levels.
As a minimum effort, change the fluid according to the manufacturers hand book.
If in doubt ... .do it anyway.

Quote Ends....................................

This test was repeated in the car park of the office I currently inhabit. Even though most of the cars there are less than three years old, only 45% of the cars tested had adequate brake fluid.

Makes you think, doesn't it?
 

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For my 9000, the book states that it should be changed every 2 years.

After owning my car for 1 year, I decided to have the fluid changed as I didn't know when it was last done.

Took it to halfords because they do it for £25.

They managed to replace about 70% of the fluid, but could bleed the offside rear caliper because the bleed nipple was seized.

I should have got the caliper sorted, but haven't yet, 10 months later.
 

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I bought my 97 CSE Anniversary 2.0 LPT 6 months back. The car was serviced by The Saab Workshop in Bristol before it was sold to me. But I don't know if the brake fluid was changed.

The RAC comprehensive check that I got did not say anything nor did the MOT inspector 2 weeks back when the car went for MOT. The level seems to be fine. How do I understand that the fluid is not in good condition and needs changing?
 

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Originally posted by neel:
[qb]The RAC comprehensive check that I got did not say anything nor did the MOT inspector 2 weeks back when the car went for MOT.    [/qb][/b]
It's not something they check for when you have an MOT. They just check for braking ability.

If in doubt, get it changed. At £25 it's worth it.
 

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Discussion Starter · #5 ·
The basic moto is:

"If you are not ABSOLUTELY SURE that it has been changed in the last two years, get it changed"

And preferably insist on DOT 5.1 fluid as it has significantly higher boiling points (dry and after some moisture absorbtion) than the Saab specified DOT 4.
 
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