change brake fluid

I have had the z3 2.3 since 1999, and have thought about changing the brake fluid by myself. According to the Bentley manual, it dosen't recommand to perform such procedure other than BMW service station. This is particularly mentioned for the model equiped with AST. Do you know why this is the concern? Thanks

2 Answers

eric64eric6424 Jan 2005
The problem with ast is that there in the brake caliber are little valves who will work with the different level of traction according for each wheel. When you will change the brakefluid yourself tou will need a special machine who will give high pulses to that valves and will avoid damage to your ast system. So i will give as advice : go yo a garage who is equipped with that special machine abd that hasn't to be a bmw dealer. I live in holland and fix bmw's and we have such a machine. The brand is ATE , Greetings , Eric
dshirleydshirley28 Jan 2004
The AST system uses the braking system in a much more advanced method than a traditional brake. One thing which AST enables is independent braking of each wheel to help in case of a spin or in case of braking where each wheel has different levels of traction. What this results in is a system which is somewhat more complex and one which is much more difficult to set up properly. If you have AST, I would really avoid changing the oil yourself unless you really know what you are doing and have the proper documentation. It's not an expensive procedure and if it does go wrong, the consequences can be catastrophic.