I suppose we've all heard crazy different viewpoints on this one. "Change your brake fluid religiously or you will die!" or "Well, there's still some in there. It should be o.k." So how are we supposed to know what to do? What are we to think about all this?
Anyone that is involved in, or aware of their vehicles maintenance has probably been exposed to the sales pitch of changing their brake fluid "for safety's sake" or "as preventive maintenance". But what's the real deal? Should we be concerned or are we getting scammed?

As usual, common sense should prevail. Being an informed and sensible consumer will usually see us through most seemingly confusing choices. So let's become informed and be sensible.

Yes, your vehicle owners manual is a good place to start. When it recommends brake fluid change as a maintenance feature you can bet that the company has reason for doing so. That reason being a matter of basic mechanics (combined with lawsuits against them no doubt!)

First; the truth is that normal corrosion from the brake system does collect in the brake fluid over time and poses a potential threat to various components of the brake system. Sometimes, no problemo. Other times, premature wear of master cylinder etc. Worse yet, although rare, complete component failure. Not good! Warning!Warning!Danger!Danger!
Second; brake fluid is "hygroscopic" (yes that's a real word) meaning that it attracts water to itself. While manufacturers and mechanics do their best not to expose the fluid to the air any longer than necessary, presto magico, your brake fluid does over time extract water from the air. But why should you care, other than impressing your friends by spelling hygroscopic in scrabble you might ask? Because higher water content in your brake fluid = lower boiling point of your brake fluid. And why should you care about that? Remember that trip to the mountains? Towing the boat. With all the kids in the truck. And coming back down the mountains, and after using your brakes repeatedly, stepping on the brakes was like stepping on a ripe plum and it scared the bejeebers out of you?! Remember, higher water content=lower boiling point, and when your brake fluid boils, the air that's in the water that's in the brake fluid forms air bubbles, and air, unlike fluids, will compress, and that is not safe.

So now that we're informed, let's be sensible.

Again, your owners manual is a good place to start. Most will recommend a time interval for brake fluid replacement. It's not a bad idea to follow the guidelines. Often, when you need new brakes the mechanic/dealer will recommend new fluid as part of the service. Scam? or Sensible? While "dip strips" supposedly indicate the "life" of the fluid, they don't address water content or even petroleum contamination. However, it doesn't make much sense to pay hundreds of dollars for a brake job and then save a couple bucks on brake fluid! Even if you only "pad slap" the sucker, skimping on new brake fluid just ain't smart.

And that's it folks, "The Lowdown On The Slowdown". Drive safe and Happy haulin'!

Learn more about this author, Ryan E. Day.
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