Brake Bleeding
 

I've read that when bleeding the brakes you need some sort of special took which removes any air bubbles caught up in the system.

Is that true ? Does the old fashioned method not work on the X5 ? As in bleed out the fluid, replace and pump the peddle while watching the bleed screw at each wheel until the bubbles stop ?

Is it really more difficult on the X or are people just being a bit pedantic ?

the special tool is GT1 diagnostics to cycle the abs pump .
this would be required if air is present in the system .
you can just change fluid the old fashioned way if there is no air in the abs pump .

I have brake fluid replaced every 2 years on my vehicles with no problems . never had to use the GT1 .

Thanks for the answer. How would you know if there was air in the abs pump ?

I would not know as you would not know .
unless you know if the system has been opened up at any place to allow air in
spongy brakes are a sign of air in the system .

If theres no air in the ABS modulator now and even you change downstream parts .like calipers,discs,pads,hoses and lines ,there is little chance of air getting into ABS when you bleed the system...I do all the time ,outside work,and never got air in the ABS system.

just make sure there's fluid in the reservior as you bleed it. once you suck air into the M/C it'll be a PITA.

When you bleed the brakes on an X5 do you have to have the engine running to activate the vaccum booster on the master cylinder?

No you do not. You can just pump the brakes till they get stiff, crack the valve, let the fluid run out. Let the pedal hit the floor. Once it does, close the valve, then let the brake up and do the entire procedure again. Do it until there aren't any air bubbles in the system.

Thanks for the info, next thing to do when I get a chance.

I bought a power bleeder to change the fluid in all of my Bimmers. It was pretty inexpensive. Makes cahanging the brake fluid easier than changing the oil...