Skip the auto shop - Our mechanics make house calls

Q: Leak in the braking system

asked by on

I think I have a leak somewhere in the braking system but I can't find any leaks. I have disc rotors in the front, drums on the back, brake fluid got down half an inch with the pads that are worn.

A: Generally, that’s the brake master cylinder...

Generally, that’s the brake master cylinder, and when they leak, they leak into the booster. So what you might try to do is take the master cylinder off and see if the inside is wet. Take a flashlight and look inside the booster and if you see fluid in there, you’ll now that it’s leaking. When it is leaking fluid and you cannot see it, it is almost always the booster when the master cylinder is leaking into the booster. You can’t see inside because it is a sealed part of the system. If you want to have this verified, I recommend getting the vehicle checked by a certified technician, such as one from YourMechanic. They will be able to diagnose the leak and determine what needs to repair.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: How does brake fluid get dirty?

One way that brake fluid becomes contaminated is when moisture is absorbed by the brake fluid through rubber brake lines. This moisture will break down the brake fluid and cause rust in the brake system. Excess moisture in brake fluid...

Q: rubbing and pulsating sounds from Left Front Wheel when turning right.

You could have two issues. The first issue that is certain is you have a bad brake rotor or two. Any time you have pulsation when braking, the rotors will need to be machined or replaced. If it is...

Q: Master cylinder and brake booster leaking

Worn master cylinder seals can cause brake fluid to leak into the brake booster, damaging it. I'm guessing this is what happened to your truck. Replacing both the master cylinder and brake booster is the only way to solve this...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.