My brake pedal went to the floor without a warning

FRANADAME

MEMBER
2006 CHEVROLET SILVERADO
4.3L
V6
2WD
AUTOMATIC
155,694 MILES

My truck was working fine and in the morning coming home from work I stepped on the brake pedal to start the engine and it went all the way to the floor.
That had never happened, so I pumped the pedal and it came up again but 20 minutes later when I got home it went to the floor again. I filled the brake reservoir it was low. And when I started the engine the pedal went down again and the fluid level went down.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,747 POSTS

Hi and thanks for using 2carpros.com.

If the fluid is disappearing, you have a leak. What I need you to do is first inspect under the vehicle for wet areas. Check along the frame and at each wheel. Also, here is a link that discusses possible causes for the pedal going to the floor:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

If you have a helper, fill the master cylinder with brake fluid and have the helper pump the brakes while you check under the vehicle for leaks. If you live in an area where there are things that can cause corrosion such as salt on the roads during winter, there is a very good chance one of the steel brake lines has rusted through.

Let me know if I can help of if you have other questions.

Joe