Technical Article |
By Bill Kuschmeider
BMW Master Technician
Advantage BMW
In cars equipped with hydro-boost brakes (750iL, 735iL, 633 and 533, for example) it is necessary to pump the brakes at least 20 times with the engine off before checking the power steering fluid level. By doing this, you raise the fluid level in the canister. If you fail to do this, you may accidently over fill the canister causing fluid to leak out. When filling the canister, use only ATF or Pettison C7.1 (check your car for the recommended fluid).
If you're not sure if your car is equipped with hydro-boost brakes, look under the hood; if you don't see a vacuum booster, you have hydro-boost brakes.