Brake discs replaced

Gus · 4th September 2003, 13:50

I've done almost 60k and the dealer is saying my front discs need replacing! Anyone else had this? (I've only had the pads changed once!)

M5 XDW · 4th September 2003, 16:02

I had mine replaced at 43000,they was warped!!The rears are looking a bit worn now at 50000.

c4m5 · 4th September 2003, 17:29

My fronts were replaced @ 60k also (to thin), I had the Euro spec floating rotors installed.

mottati · 4th September 2003, 18:35

Based on my past experience with bmw (non m cars however) that sounds like pretty good rotor life! Most of the time, the rotors and pads tend to get replaced at the same time, as I've been told the rotors would be past their minimum thickness around the same time as the second set of pads are about half way worn down. Maybe the M5 rotors are beefier, and last longer, but 60k seems like pretty good life. I had usually gotten around 20-25k on a set of rotors and pads, with some track time (and track pads) on my 528 (with larger 540 brakes)...
60k certainly sounds reasonable to me...
Mike
00 M5 titan silver, imola/black sportiv
98 528i
03 LandCruiser

kiwi M & M · 4th September 2003, 19:49

Quote:

Originally posted by mottati
. I had usually gotten around 20-25k on a set of rotors and pads, with some track time (and track pads) on my 528 (with larger 540 brakes)...
60k certainly sounds reasonable to me...
Mike
00 M5 titan silver, imola/black sportiv
98 528i
03 LandCruiser

Correct me if I'm wrong, but track pads do wear the rotors down a lot faster than stock pads. Having said that, my 95 M3 rotors were replaced twice during my 70k ownership with original bmw pads

. Need stoptech rotors and pads...

-Jay

mottati · 4th September 2003, 20:51

you are correct, some track pads can eat up rotors, but even prior to using them, my rotors seemed to be pretty worn down, with a significant 'ridge' at the edge, after on set of stock bmw jurid or textar pads (usually around 25k, with maybe 2 or 3 weekends at the track).
Mike

4th September 2003, 23:17

I could be wrong, but i was under the assumption the BMW used fairly soft rotors, and that they didnt lead the longest life. My old E39 528 ate pads at 45k, with a recomended rotor replacement (I didnt track it, but ran it hard through the twisties every day). So, 60k for a beast sounds reasonable to me. My mothers e34 525 took rotors at 75k, but she drives like someone in their 90s, so they led an easy life
Enjoy the beast!

DZeckhausen · 5th September 2003, 07:56

Quote:

Originally posted by BmwNut
I could be wrong, but i was under the assumption the BMW used fairly soft rotors, and that they didnt lead the longest life.

They don't use "soft" rotors. The metallurgy of rotors is very similar across the different car brands. Everyone uses grey iron for rotors with minor tweaks of the impurities to trade off different characterisitics, such as strength for susceptibility to pad deposition.

The BMW rotors have thinner friction plates than Mercedes and other brands. BMW allows 1.6mm of total rotor wear, whereas Mercedes allows 2.4mm. Thus, Mercedes rotors tend to last longer than BMW rotors. Nothing to do with the compostion of the iron. BMW trades off larger air gap (better cooling) for thinner friction plates (shorter life).

Need4Spd · 5th September 2003, 18:19

Does anyone make cross drilled rotors that are direct replacements for stock rotors for our cars? I know the cross-drilling is just to look cool, but... inquiring minds want to know! Zimmerman makes nice ones, but I don't think they have an application for the M5, or do they?

ColinM · 5th September 2003, 18:35

My discs cause vibration through the steering wheel under braking which I guess is caused by warping or pad material on the surface. The car has done 44000 miles.
Is it worth skimming the discs and then using new better pads instead of buying new discs ?