The brake master cylinder is responsible for distributing fluid from the reservoir to the front and rear brake systems. The fluid reservoir actually sits on top of the master cylinder with hard metal brake lines running out of it. There are a few places where the master cylinder can leak and cause a spongy or soft brake pedal. The inside has several pistons with o-rings and seals that can fail and allow brake fluid to escape. Likewise, the external metal lines also have o-rings where fluid can seep out or let air/moisture in.
This is an OEM replacement brake master cylinder that fits many E53 X5 models. If your original BMW brake master cylinder has failed, this is the high quality replacement you need.
This item fits the following BMWs: 2002-2006 E53 BMW X5 3.0i X5 4.4i X5 4.6is X5 4.8is Show More Show Less
