Rotors - United Bimmer Community

**Butterfly** · 05-02-2007, 06:56 PM

Alright I'm replacing my front rotors and pads, but was warned about bmw's leaking it's brake fluid into the system and breaking it. Now how is this prevented? i plan to follow the guide on this forum and having a friend who has done a few German cars but never a bmw.

thanks

**RSF5** · 05-02-2007, 07:23 PM

I haven't heard a lot about BMWs leaking brake fluid...?

**NavyL7** · 05-02-2007, 07:32 PM

what do you mean by "leaking brake fluid into the system and breaking it" ?? Do you mean leaking from the calipers?

**mullethunter3** · 05-02-2007, 07:39 PM

Yeah, in my experience, the fluid system is very tight and sound. I've been in there twice on two different car and can't seem to think of a place that might leak fluid and "break" the system.

**RSF5** · 05-02-2007, 08:04 PM

Anyone else heard of this??

**215BIMMER535** · 05-02-2007, 08:29 PM

never. i've done my brakes twice. once was all new rotors and pads. once just all new pads. granted, theres a warning in the manuals about overflowing the reservoir when u drive the piston back in, and it overflowing..... but that is the only thing i've heard of even remotely sounding like what u said, and mine wasn't even close to overflowing. take your time, follow directions, and you'll be fine. the brakes on these cars are really simple

**Butterfly** · 05-02-2007, 09:50 PM

alright thanks for the help.

drz · 05-02-2007, 10:33 PM

Be sure to follow the directions in the DIY -- do not let the calipers hang on the brake lines, because THAT could break them.

ENjoy bimmerDIYing

**jdgoff** · 05-07-2007, 09:37 PM

What year? My 92 has brakes just like nearly all other production disk types. I've done my front brakes 3 times, and last time replaced flex hose with after market stainless protected hoses. Need one on each side. Otherwise, I think std OEM hose replacement should be OK. Your friend should find his experience can be safely used on BMWs. Do be careful not to cross thread hard and flex hoses. Also I suggest you use flare nut wrench on fittings. These are not very expensive, and available at most parts stores. If you do replace hoses, you must bleed brake lines. Nothing tricky here if use two person technique. Ask friend. Sequence FR then FL, if only front axel replacement.

**jdgoff** · 05-07-2007, 09:42 PM

Had another thought. Check caliper cylinders for leakage. If they leak, should see brake fluid all over. preventative maint. would be to replace or rebuild. It is a messy job, and I wouldn't recommend it unless you have tech manual and sufficient tools.