While changing brake fluid is probably a good idea, I'm dubious about the possibility of moisture boiling and causing a loss of braking action. I'd guess the major benefit of changing fluid regularly is corrosion prevention. Although there might be other cars with recommended brake fluid change intervals, Volvo is the only one I've ever encountered. Most cars get a brake fluid change (of sorts) only when the brakes are bled after caliper or wheel cylinder maintenance.

Thank you everybody for your precious hints. Monday morning, I am going to make an appointment with my dealer for a spring tune up. I will ask about changing the brake fluid

> I am wondering what it means. Is it really useful ? Is it worth the

> money it will cost ? What could happen if I do not have it done ?

> I would like to know if anybody has an opinion about this matter or

> has

> ever done it.

Is it useful: Yes. It's your safety we're talking about here!

What could happen if I do not have it done: if the fluid is old it will have absorbed a large amount of moisture, which lowers it's boiling point pretty drastically.

If you brake hard (emergency stop) or drive down a mountain (regular braking) the moisture which has gotten into the fluid will start to make it boil. This will give air bubbles in the brake lines. This causes loss of braking power as air compresses... As Ray pointed out can dirty brake fluid also cause problems in some (very expensisve) ABS parts.

Milage is not very important, age is. Every second of every day the fluid will be slowly sucking in humidity from the air. Use it or not. Also one of the reasons that an opened container of brake-fluid can only be stored for 1 to 2 months before having to be thrown away.

If you were living in a hot, dry climate you may be able to safely extend this period, but in a wet, cold climate I would even lean towards a flush every year. If you drive fast (and need to brake hard often) or in the mountains then I'd definitely go for a yearly flush.

I always have my brake system flushed every 2 years (irrespective of milage) and I definitely feel the difference. More positive braking and less 'fuzzyness' when braking longer. I'd call a few $$ for a flush good preventive maintenance. As a side-effect you probably will never have problems with bleed-screws getting stuck because they haven't been used in year..

Bye, Arno.

Brake fluid can absorb moisture (it is very hydroscopic) which

can cause problems when the brake fluid heats and the water boils

(you get air in the lines and poor braking). Also, keeping the

fluid fresh is supposed to lengthen the life of the ABS

components which are very expensive to replace (I suspect it

is more of a case of dirty fluid shortening the life of ABS parts).

If you live in a dry climate you may be able to go with a longer

time between changes. I've yet to do this on my 4 year old

98 but will within the next couple months as it hits 30K miles.

Dealer where I service our Volvos at includes this in the 30K

and 60K services and does not break the price out (so I can't

say what it would cost).