rene525d

A friend of mine has a problem which he asked me about, and i never noticed this .... maybe anyone has any idea.

When travelling fast (over 100km/h) the brake pedal feels hard and much more force needs to be applied to stop the car. If he then hits the pedal too hard, ABS kicks in even on dry roads. This only happen at fast speeds and not during normal city driving.

He also said that with the engine running, and the car in idle, after 2-3 presses of the brake, the pedal hardens just like when the engine is not running. Any ideas?

rkoenig

Which model is he driving? Sounds like it could be related to the recent recall actions.

rene525d

Dont think soo.... Its a 530d 2006 pre lci

turboawd

sounds like hes losing vacuum assist to the brakes. either a bad booster, or problem with the vaccum lines.

or does the diesel version use hydraulic assist??

adriana

I dunno about E60, but I experienced this with my E46. It was the vacuum thingy. I had to replace it. Perhaps he can get any shop with OBD II reader to see if there's any error code? Brake is a very serious part, and he should bring the car to a repair shop immediately

rene525d

thanks will let him know. Great forum as usual!

toyota2bmw

If the pedal hardens, that either means the vacuum pump is NOT producing vacuum into the line and/or the brake booster is not holding the vacuum produced by the pump. Either case, you should have it checked out immediately.

YeeeHaa

If he car has never had the brake fluid flushed and replaced then the brakes start to become "spongey". After the spongey stage the brakes will require more effort to stop the car.

First thing to do is change the brake fluid and test. ?80.

BMW recommend changing the brake fluid every 2 years.