Brake fluid in the bay: we check it, we advise, we do not repair

People sometimes wonder why a bay would check something it does not service. It is a fair question. The answer is that brake fluid is one of the easiest things on a car to check and one of the most important to know about, and you deserve to hear about it even when the fix is somebody else's job.

What brake fluid does

Your brake pedal does not push the brakes directly. It pushes fluid through lines to the calipers or wheel cylinders at each wheel, and that fluid does the squeezing. Because liquids barely compress, the pedal feels firm and the brakes respond immediately.

Most brake fluids are hygroscopic, which means they absorb moisture from the air over time. The Car Care Council notes that brake fluid absorbs moisture and should be inspected and replaced as the owner's manual directs (Car Care Council). Moisture lowers the fluid's boiling point, and boiling fluid makes vapor bubbles, which compress. That is the spongy pedal on a long downhill.

What we check

Brake fluid is part of the maintenance check. The technician looks at the reservoir level against the marks and at the fluid's color through the reservoir. New fluid is usually clear to light amber. Old fluid darkens. A level that has dropped can mean the pads have worn, since the fluid moves to fill the space as pads get thinner, or it can mean a leak.

Either way, you hear what we saw, in plain words.

• Level at the full mark and fluid clear: nothing to report
• Fluid dark or cloudy: worth having a brake shop test and replace it
• Level low: pads may be worn or there may be a leak; get the brakes inspected
• Pedal soft, warning light on or grinding: see a brake shop soon

What we do not do, and why we say so

We do not flush brake fluid, replace pads or rotors, or repair brake lines. Our service centers focus on oil changes, fluid services for the engine, transmission, differential, cooling and power steering systems, filters, A/C, bulbs, wipers and smog checks at the Reno service centers. Brakes are a safety system that deserves a service center that does brakes all day.

That is the same honesty reviewers mention about other services. Cathy B. wrote that at the Carson City service center she was fully informed of additional issues found on the vehicle and advised of options with no pressure (Google review). Being told where to go is part of being informed.

Why it matters on our roads

Brakes work hardest on long downgrades, and Northern Nevada has plenty: the Mount Rose Highway down to Incline Village or back into Reno, Kingsbury Grade into the Carson Valley, Geiger Grade, and I-80 down from Donner Summit. Using a lower gear on long descents, as many owner's manuals advise, keeps brake temperatures down. Fresh fluid with a high boiling point is the other half.

So the next time you are in for an oil change at any of our four service centers, listen for the brake fluid line in the report. If it says all good, enjoy the mountains. If it says see a brake shop, take that seriously.