Dear Tom and Ray:
After 25 years of faithfully patronizing my highly competent mechanics, I fear that they are getting nervous about their approaching retirement. I have always trusted them, and they have always done a great job for me. This week, when my vehicle was in for its annual state inspection, they called to say that it had passed, but they recommended a few "services." When they got to suggesting that they wanted to "flush out the brake lines and replace the brake fluid," it took all my strength to resist going ballistic. They mentioned the tendency of brake fluid to absorb water and said that ABS systems are particularly sensitive to it. I was devastated. I thought that after 25 years, they had more respect for my automotive IQ. I have never flushed out and replaced my brake fluid, nor had anybody ever made such a preposterous suggestion. I considered it to be like suggesting that they replace the air in my tires! Being an open-minded guy, however, I wanted to get an expert opinion. Are they just stretching to pad their retirement funds, or should I take their preposterous suggestion seriously? — Steve
Ray: Steve, I wish I had 100 customers like you. I've got 200 now.
Tom: Your mechanic is absolutely right. You don't say what kind of car you have, but most manufacturers now recommend flushing and replacing the brake fluid at regular intervals — often every two years or 30,000 miles.
Ray: Brake fluid absorbs any moisture that gets into the brake system, and it holds that moisture in suspension. But eventually the brake fluid gets to a point where it can't hold any more moisture. And then you're in danger of rusting your brake components from the inside, or having brake fluid that's susceptible to boiling under hard braking conditions.
Tom: And as your wise, honest and trustworthy mechanic told you, anti-lock braking system modules are particularly susceptible to moisture. They're also very expensive to replace.
Ray: So call your mechanic, Steve. Apologize profusely for accusing him of trying to rip you off — even if you only muttered it under your breath — and thank him for letting you know that you are overdue for a brake-line flush. Then bring him some fresh, high-quality baked goods when you pick up your car, and we'll consider the matter forgotten.
(Car Talk is a nationally syndicated column by automotive experts (and brothers) Tom and Ray Magliozzi. Write to them at the Car Talk website.)