Brake pedal slowly drops nearly to the floor when applying pressure?

2003 DODGE DURANGO

107,000 MILES • 4.7L • V8 • 2WD • AUTOMATIC

TESS1253

MEMBER
1 POST
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Several days ago, I was driving and while waiting at a stop light the brake pedal began to slowly drop almost to the floor. As I continued to drive, I had to pump the brakes repeatedly to get the pressure back up. I took it to a shop. They replaced the rear brakes and changed brake fluid. The problem continued. They replaced the master cylinder and bled the brakes repeatedly. Problem continued. Took it to another mechanic who trouble shooted for 2 days, bleeding brakes, etc. Still no resolution. Does anyone have any idea what the problem could be?

Sep 9, 2023 at 12:19 PM

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JACOBANDNICKOLAS

CAR REPAIR CONTRIBUTOR
110,190 POSTS

Hi,

When the brake pedal does this, normally there is either a leaking hose, faulty brake master cylinder, or a rubber brake hose.

If you turn the engine off and pump up the brakes and then hold pressure on it, does it slowly go to the floor?

Do me a favor. Have a helper pump the brakes and hold pressure on the pedal while you inspect the rubber brake hoses at the brake calipers. Make sure they aren't expanding.

Let me know.

joe

Sep 9, 2023 at 9:37 PM