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View Full Version : Disc rubbing - wheel not turning freely?



e34.535i.sport
05-01-2007, 03:42 PM
Hi, found a bit of a problem when i removed my wheels to paint the calipers recently. :(

It seems that my drivers side front wheel is not turning freely. When the car was jacked up i tried to turn the wheel and it turns freely for about half a turn, and then is noticably stiffer for the other half. There was also a rubbing sound as i did it. I had a good look and the brake pad looked very close to the disc but i haven't really got much experience with brakes etc so im at a loss. I'm new to car home maintenance!

If anyone knows what my problem is that would be a great help, and if you can give me an idea of how to fix it or expected cost it would be most appreciated.

Thanks in advance!

rob101
05-01-2007, 03:44 PM
Hi, found a bit of a problem when i removed my wheels to paint the calipers recently. :(

It seems that my drivers side front wheel is not turning freely. When the car was jacked up i tried to turn the wheel and it turns freely for about half a turn, and then is noticably stiffer for the other half. There was also a rubbing sound as i did it. I had a good look and the brake pad looked very close to the disc but i haven't really got much experience with brakes etc so im at a loss. I'm new to car home maintenance!

If anyone knows what my problem is that would be a great help, and if you can give me an idea of how to fix it or expected cost it would be most appreciated.

Thanks in advance!
thats normal, unless you have had an incident where the brakes were smoking like a chimney after driving around don't worry about it.

DaveVoorhis
05-01-2007, 03:51 PM
If you can turn the hub by hand through the stiffer bit, it's okay.

rob101
05-01-2007, 03:56 PM
exactly, I've replaced my 2 front discs for my e34 as well as that we noticed the same thing after my father rebuilt the caliper pistons on my e28. I think its caused by the fact that the retaining screw is only on one side, so the discs sit slightly crooked since neither the piston or caliper is floating it makes one side harder to turn.

DaveVoorhis
05-01-2007, 04:23 PM
Keep in mind there's nothing in the brake system to retract the brake pads. Retraction is dependent entirely on the fact that when you let off the pedal there's (a) no pressure in the system, and (b) minute but normal variations in disc thickness and straightness will push the pads back. Thus, there will always be a spot where the pads rub.

gale
05-01-2007, 07:03 PM
I agree with how Dave summarized it. In addition to that, aged rubber brake lines can swell when under pressure (while braking) and when you let off of the brakes, there can be a slight parasitic pressure remaining in the system. My 356A used to do that really bad & new rubber brake lines solved it.

e34.535i.sport
05-02-2007, 03:20 PM
Thanks all for your input, much appreciated! :D

[V-pleased all is well! I've had this car for only a couple of months (previously had an e46), and said i wouln't get paranoid about things going wrong on this one when i got it... But im even worse! (Unsurprisingly i love this car so much more!)]

Thanks again!

Jon K
05-02-2007, 04:45 PM
The pistons engage but don't always retract by themselves off the rotor surface, in fact, when you drive, the turbulence between the rotor and pad surface creates a pocket of gas that the pad rides on, thats why if you're going into a turn at, say 170 mph and you need to brake like stink, you should clear the pads with a slight tap and left off before you actually get into the brakes.

Just kidding about the 170 part.