EvolutionVIII

I was recently having brake issues with my 2005 545i with 116,000 miles. Car was losing brake pressure after sitting at a light. As soon as I reved the engine, the brakes felt better but would instantly lose the vacuum it felt like. Took it to BMW of manhattan and they told me the brake booster was bad and that the vacuum pump was ok but leaking oil a little. I had the booster done because i had a warranty on the car through a company that covered the booster but not the vacuum pump or the seal. I picked up car today and brakes are fine now but I want to replace the seal myself. Should I just replace the pump since its off with the seal or just the seal since BMW said its good.

turboawd

there is a thread on here if you search, where i removed the cover and just applied some rtv sealant on the oring and fixed the leak. didnt cost me anything but my time.

e6t.lab.rat

^^ What he said . I used this thread to re-seal the o-ring last week in my 05 545 and no leak since.

https://5series.net/forums/e60-discu...-common-91247/

EvolutionVIII

Was it the o ring inside the pump behind the cover with 5 torx screws or the o ring when you removed the entire pump?

EvolutionVIII

Found this in the post you gave me. Gonna just do both with these replacements
BMW 2004 545i Brake Booster Vacuum Pump Seal Kit 11 66 7 545 384 305162

How do you know if the pump is going bad. BMW said its fine,just leaking....

turboawd

usually the oring behind the cover with the torx screws is what goes bad. it seems the oring loses its shape with time.


hopefully that oring is a different rubber compound that doesnt lose its elastisity or shape with age.

if the pump was going bad, you wouldnt have any power brakes.