View Single Post
      11-06-2012, 05:07 AM   #19
No 55mph
1QuikWS6's Avatar

Drives: 09 E92 328iX N51 3-Stage ->M6
Join Date: Jul 2009
Location: Blitzburgh, PA

iTrader: (87)

Garage List
Well, I can see a ton of mechanics making $$ for nothin here - NEVER in my life have I heard that you need to bleed your brakes after a pad change & it is definitely not necessary...

> Only time you need to bleed brakes is if the system has been opened to the air, such as disconnecting a brake line, or replacing a master cylinder/caliper, etc.

> And opening up the cap on your reservoir doesn't introduce air into the system either (unless you have no fluid in there and pump the pedal).

I've been changing my own pads, on more different cars that I have owned, than I can remember, since 1976 & have NEVER bled the brakes after simple pad change.

> If the brakes didn't need bled before the change, they don't after. It isn't even needed as routine maintenance - if there is no air leak in your system there is no way for the air to enter.

> Now, I agree that brake system needs to be completely flushed/refilled with fresh fluid every 2 yrs - but this is only to refresh the fluid which can/will absorb water over time.

> Pushing the caliper piston back in to housing to allow for new thicker pads does not let air into the system - the piston is sealed in bore. If moving the piston added air - then every time you use the brakes air would enter.

> Air in your system does not result in your pedal going to the floor either. Air in the system gives you a 'spongy' feel when you apply the brakes - as air is not compressible in a hydraulic system.

> Pads that are not 'bedded in' don't result in pedal going to floor either. Bedding in simply transfers pad material to the rotor (if done correctly) to enhance braking ability. Mostly this is done with aftermarket hi performance pads - not OEM. Hell, there are tons of pads being changed every day by dealers (including BMW), or ind. shops that are never bedded in. They change your brakes - you pay - get in the car & drive off. All (4) of my rotors/pads have been changed under warranty with OEM, nary a mention on needing bedded in, and brake performance is as when new.

As mentioned, you always start car, pump up brakes after a pad change - simply to move piston/pad combo back out into contact with rotor after you have retracted the piston fully during swap. This should take like 3-5 pumps on the pedal max, not 5 minutes of pumping.

If it took you 5 min to get any pedal feel, and then they still weren't good upon 1st use - then you have problems other than what can be fixed by a simple pad change.
2009 328ix E92//SGM//ACS Roof Spoiler//MTech Aero Lip+Trunk Spoiler//M3 Side Skirts//CF Roundels+Grilles//M3 Novillo Interior//Perf Shift Lever+Boot//MPerf DCT Wheel//M3 GT3 eBrake Handle+Boot//ACS Pedals//M3 Mirrors//LCI Tails w/LUX Rev//LUX 160 AE+MTec 6000K D1S+HPB HID 6000K Fogs//HPB LED Interior//RPI Scoops//CF Euro Airbox+Underhood Hsgs//K&N//BMW PE//MTech Rear Bumper-iS Sport Diffuser//CF Strut Brace//Vishnu OFT//BMW 193M's+Kumho 4X

Last edited by 1QuikWS6; 11-06-2012 at 06:00 AM.