Hi there, a bit of a newbie question.
My E39 has 48k miles and during the last service the dealer said that the
brakes may need to be done (fr & rear) on it's next service at a cost of
£300 Front and £375 rear.
I'm thinking of doing it myself and have 3 questions :
1. Is it a difficult job and are any special tools required?
2. Would I need to change the rotor motors, how would I know whether they'd
need changing?
3. Any recommended brake manfucaturers (I'm assuming I won't be able to buy
'BMW' brakes from an brake specialist)?
Any help or links to help would be appreciated.
Thanks
Matt
Mike G - 27 Aug 2005 02:38 GMT
> Hi there, a bit of a newbie question.
>
[quoted text clipped - 5 lines]
>
> 1. Is it a difficult job and are any special tools required?
Changing brake pads is an easy job. If you consider a 7mm hexagon key a
special tool that's probably all you'll need.
> 2. Would I need to change the rotor motors, how would I know whether they'd
> need changing?
Check the thickness/width on the worn area with a micrometer or vernier,
against the recommended minimum, but if they have a heavy lip on the outside
edge, or are heavily scored, change them anyway.
> 3. Any recommended brake manfucaturers (I'm assuming I won't be able to buy
> 'BMW' brakes from an brake specialist)?
>
> Any help or links to help would be appreciated.
Try one of these for decent pattern parts.
http://www.brakeparts.co.uk/
http://www.gsfcarparts.com
http://www.eurocarparts.com/
Looks like if you DIY the job, you can buy everything you need. New pads and
discs all round, for £150-£200.
My advice is go for it. It's one of the simplest of maintenance tasks.
Probably no more than half an hour to change discs and pads on the front and
the same for the back, so even allowing for inexperience, you should get the
job done in a couple of hours.
Ask in one of the BMW forums if you need precise details of how to do it.
Or maybe someone in this n/g might know. I have an E34, but I hesitate to
say that an E39 is exactly the same.
Mike.
John Carrier - 27 Aug 2005 12:36 GMT
Pretty easy job. Add a C-clamp to your tool list to simplify pushing the
pistons back into the calipers. Clean the calipers and lube the pins before
reassembly. Buy a quart of Ate fluid and flush the whole system during the
bleeding.
R / John
> Hi there, a bit of a newbie question.
>
[quoted text clipped - 14 lines]
> Thanks
> Matt
Philip K - 28 Aug 2005 13:50 GMT
>Pretty easy job. Add a C-clamp to your tool list to simplify pushing the
>pistons back into the calipers.
C clamp really is a kludge - yes, I've done it but you can only push one
piston back in at a time. It's well worth buying a proper brake caliper
retraction tool (I think Halfords do a Draper one for under a tenner)
which pushes both pistons back in at the same time and doesn't risk
tearing the seals.

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Malt_Hound - 28 Aug 2005 15:29 GMT
>>Pretty easy job. Add a C-clamp to your tool list to simplify pushing the
>>pistons back into the calipers.
[quoted text clipped - 4 lines]
> which pushes both pistons back in at the same time and doesn't risk
> tearing the seals.
Well, most cars only have one piston, but either way, what you do is
leave the one (piston side) brake pad in and press against that. That
way you exert even force so that the pistons don't get cocked in their
bore(s).
No risk. Works perfect every time.

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-Fred W
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Dave Plowman (News) - 30 Aug 2005 00:05 GMT
> C clamp really is a kludge - yes, I've done it but you can only push one
> piston back in at a time.
The majority of modern BMWs have only one piston per caliper.

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J Strickland - 29 Aug 2005 19:27 GMT
I use a large screwdriver to open the calipers before I take them off. I
find this easier than the c-clamp method. Of course, one has to be careful
to not harm any of the seals and such ...
> Pretty easy job. Add a C-clamp to your tool list to simplify pushing the
> pistons back into the calipers. Clean the calipers and lube the pins
[quoted text clipped - 21 lines]
>> Thanks
>> Matt
Malt_Hound - 29 Aug 2005 22:37 GMT
> I use a large screwdriver to open the calipers before I take them off. I
> find this easier than the c-clamp method. Of course, one has to be careful
> to not harm any of the seals and such ...
Bad idea for a coupel of reasons, Jeff.
1) You might ding the rotor whilst prying, and
2) You put pressure on only one side of the piston. If it is at all
worn, you risk cocking the piston in the bore and then you'll be
shopping for new calipers.
It really is very easy and painless to do it with a big C-clamp or the
tool made for the job.

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-Fred W
Toys for sale, Hey get your toys here:
<http://users.adelphia.net/~fredwills/>
J Strickland - 29 Aug 2005 19:25 GMT
> Hi there, a bit of a newbie question.
>
[quoted text clipped - 5 lines]
>
> 1. Is it a difficult job and are any special tools required?
No, it isn't difficult, and no you don't need any special tools.
> 2. Would I need to change the rotor motors, how would I know whether
> they'd need changing?
Here is an opportunity for a special tool, you may need a micrometer or a
set of calipers to measure the rotor thickness. I would not guess that you
need rotors after only 48k miles.
> 3. Any recommended brake manfucaturers (I'm assuming I won't be able to
> buy 'BMW' brakes from an brake specialist)?
I used Raybestos Professional Grade pads on my car when I installed them the
last time. They were MUCH cleaner than the pads that came off, which I don't
remember what type they were but they were very dusty. One problem with dust
free pads is that they are a bit harder than the dust making pads, and the
problem with the hard pads is they tend to be noisy (squeal) when the brakes
are applied lightly - which is the way I use my brakes about 90% of the
time. You get a little noise, but no dust. You gotta decide if the trade off
is worth it. I think it is.
Malt_Hound - 29 Aug 2005 22:35 GMT
>>Hi there, a bit of a newbie question.
>>
[quoted text clipped - 26 lines]
> time. You get a little noise, but no dust. You gotta decide if the trade off
> is worth it. I think it is.
Hmmmm.... That's contrary to what I have always beieved, and
experienced. Not about the Raybestos PG's, I put those on my Jeep
Wrangler and they worked very well with little dust.
But pads... a different car, maybe a different dimension, but on SAABs
where I have way too much exprience changing brake parts. I switched
from factory SAAB pads (good but dusty) to Pagid OE pads (same) to Axxis
PBR deluxe pads (organic not metallic) gave slightly less responsivenes
but significantly less dust. Those puppies were definitely soft. One
time I took some pads off and roughed them up with some sandpaper (don't
try this at home with asbestos pads kids) and you could really tell the
difference.
Anyway, the lowest dusting pads don't *have* to be the hardest ones.

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Toys for sale, Hey get your toys here:
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Jeff Strickland - 30 Aug 2005 17:00 GMT
>>>Hi there, a bit of a newbie question.
>>>
[quoted text clipped - 40 lines]
>
> Anyway, the lowest dusting pads don't *have* to be the hardest ones.
OK. My logic says that low dust will come from harder pads, high dust from
softer pads. Remember, that's logic speaking, not science. I know that my
Raybestos pads were clean as a whistle, and they were noisy. I assumed the
noise and the low dust were related by hardness of the pad material.
C.R. Krieger - 30 Aug 2005 23:13 GMT
> Here is an opportunity for a special tool, you may need a micrometer or a
> set of calipers to measure the rotor thickness.
Ah, here my friend Mr. Strickland hits the point!
AIN'T NO JOB WORTH DOIN' UNLESS YOU CAN JUSTIFY THE PURCHASE OF AT
LEAST ONE NEW TOOL!
--
C.R. Krieger
(Ask my wife!)
Bob - 31 Aug 2005 01:42 GMT
>>Here is an opportunity for a special tool, you may need a micrometer or a
>>set of calipers to measure the rotor thickness.
[quoted text clipped - 6 lines]
> C.R. Krieger
> (Ask my wife!)
(Jumping out of lurker mode)
Sorry to quote the entire point but it is a really, really good point
and one that should not be shared on a (potentially) insecure thread. I
do not want to lose this privilege in future... ;)
Bob Balbirnie
(and please: don't ask mine!)