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Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 5 Series > E39 (1997 - 2003)

E39 (1997 - 2003)
The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

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  #76  
Old 03-16-2008, 10:42 AM
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Quote:
Originally Posted by PJB. View Post
The dictionary says that the etymology of the word comes from the Greek "micros" meaning small, and "metros" meaning measure. Makes sense.
Than, what does "inchos" and "feetos" mean in Greek?

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  #77  
Old 03-16-2008, 11:43 AM
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Originally Posted by MatWiz View Post
Than, what does "inchos" and "feetos" mean in Greek?

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I'm pretty sure "feetos" has something to do with corn chips.
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  #78  
Old 03-16-2008, 11:56 AM
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Originally Posted by PJB. View Post
I'm pretty sure "feetos" has something to do with corn chips.
Nah.. "inchos" is more likely to have something with corn chips. "feetos" is the hot souce.

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  #79  
Old 03-18-2008, 06:15 PM
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As soon as I landed in SFO from Hong Kong, I ordered the parts.

Given all the possible scenarios, I went with as close to OEM as possible, and will soon receive four new rotors (yes, I'll redo the rear even though they are technically well within spec), two new sensors, front and rear pads, anti-seize, and a liter of non DOT4 (due to opacity) ATE (apparently pronounced ah tay) brake fluid for the optional bleeding once I'm done.

At the moment, I don't have any major questions except what to do about the rear parking brake, but, I'm assuming that will somehow take care of itself once I get the rear rotors off.
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  #80  
Old 03-18-2008, 08:46 PM
dvsgene dvsgene is offline
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WELCOME BACK BLUEBEE. Thought you gave up on the project but good to hear you opted to replace the "technically within spec" rear rotors. That's what I would have done.

Good luck with it. Any other questions, we're here to add our two cents.....
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  #81  
Old 03-25-2008, 01:56 AM
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Quote:
Thought you gave up on the project but good to hear you opted to replace the "technically within spec" rear rotors
Hi guys,
I have been very busy so I didn't get a chance to report back that I'm done with the 4-wheel brake job (rotors, discs, and sensors).

A friend came over Saturday to lend me some tools, and, we did all four wheels in the space of an afternoon. Some tasks, such as wheel cleaning spilled into the evening, but, the brakes are all in. I have to learn how to bed them so I've been driving gingerly until I figure that out.

To help the NEXT person, I snapped over 600 photos, covering each step of the way - and am now pondering how I am ever going to write that extensive DIY that I wish I had before I started.

Yes, I know there are other DIYs out there but NONE (and believe me, I've looked), none tell the complete story.

As just one example, I don't know if any tell you that the rear well is definitely in the way of connecting the rear brake sensor to the wiring harness. Pity that I had lovely silver anti-seize goop all over the rotors and anti-squeal glop all over the calipers when I was forced to muck with that horribly dirty plastic wheel well spilling cruft all over my nicely cleaned and lubricated brake parts!
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  #82  
Old 03-25-2008, 02:22 AM
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Nobody tells you which DIRECTION to turn the parking brake star nuts!

Likewise, as far as I remember, nobody told me which DIRECTION to turn the star nuts in order to contract the brake shoes completely and then turn the star nut in the expansion direction for 12 clicks to begin the parking-brake adjustment procedures!

Since I learned all this the hard way, I'd like to write up a complete DIY that covers all the nuances that I ran into on my very first BMW brake job.

I don't know if I'll ever have the time to write that DIY as it takes an extensive amount of time to document each step ... but here's a sample set of pictures showing how it works.

BTW, I wonder if anyone actually performs this recommended parking brake adjustment judging from the DIYs I've seen so far ... Maybe I'm the only idiot who followed the manual? ... In hindsight, I wish I had left the parking brake adjustment alone! (nobody told me this!).

Parking brake shoes fully contracted:



Parking brake shoes expanded:
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  #83  
Old 03-25-2008, 02:34 AM
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Don't even try to remove the brake wear sensor while the calipers are still on!

Another faux pas I committed was to try to remove the brake wear sensor without first removing the calipers from the wheel!

The perfectly good wear sensor shredded itself rather than leave the warm cozy confines of the notched brake pad. In hindsight, I would have removed the caliper first, then pried the brake wear sensor out with a small flat-head screwdriver rather than use pliars to yank the wear sensor out prior to removing the calipers.

Someone said earlier, no matter what you do, mistakes will be made. I just want the next person who does their very first BMW E39 brake wear sensor replacement to learn from my (pictorial) mistakes.

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  #84  
Old 03-25-2008, 02:59 AM
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Nobody tells you the brake wear sensor wires are too short by default

As just another example, nobody tells you the front brake wear sensor long wires are just too short out of the box to fit in the harness-connection box!

This is hard to explain, but, you have to have the courage to pull and tug more than gently on the sensor wires at the harness-connector end until the two wires all of a sudden SNAP sickeningly a good two inches out of somewhere (I don't know if the wire was coiled inside the harness cap or if it was slack inside the long wire).

Yikes!

It seems to me, that, without pulling the wires out of their hiding place, you'll never get both the harness connector and the ringed grommet above the harness connector to seat properly in the black case for the front brake wear sensor harness connector.

Why doesn't someone mention that in their brake DIY?
Well, if/when I ever write it, I certainly will make note of it!



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  #85  
Old 03-25-2008, 05:08 AM
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Congratulations, bluebee!

About the sensor. I don't remember ever needing to pull the wires out of the brake sensor housing. Is is possible you had the wrong part? I don't remember if the front & rear are different length, but the size of the plastic housing look different in your pictures.

About breaking the sensor when you pull it out. You need to pull it strait out of the pad. Because of the L shape of the sensor, it tend to be pulled sideway, and that is when it will break. If you pull it strait up, it will not break.

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Last edited by MatWiz; 03-25-2008 at 05:11 AM.
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  #86  
Old 03-25-2008, 08:36 AM
larobj63 larobj63 is offline
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Three spreadsheets, two pie charts, a gnant chart, and 5 pages of reports later, she'll wind up replacing them.
Ah ha!!! Told ya so!
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  #87  
Old 03-25-2008, 03:17 PM
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Quote:
Originally Posted by bluebee View Post
To help the NEXT person, I snapped over 600 photos, covering each step of the way - and am now pondering how I am ever going to write that extensive DIY that I wish I had before I started.

Yes, I know there are other DIYs out there but NONE (and believe me, I've looked), none tell the complete story.
And perhaps that's why it's never been done. BUT if you do get around to writing it up in Detail and with pics, you'll bring this forum to a whole NEW LEVEL. GO BLUEBEE!


Quote:
Originally Posted by bluebee View Post
Someone said earlier, no matter what you do, mistakes will be made. I just want the next person who does their very first BMW E39 brake wear sensor replacement to learn from my (pictorial) mistakes.
Being that the majority of members on this forum are men, most would rather "wing it" and learn as you go. I would say the majority of guys here are the type-"when opening something new that needs assembling" toss aside the instruction manual and "wing it" only to open the manual if they are stuck. I think it's a man thing. But don't let that hinder you from posting the detailed write up!

Last edited by dvsgene; 03-25-2008 at 03:23 PM.
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  #88  
Old 03-25-2008, 03:23 PM
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Since you found out that there is not even one DIY for the hand brake...

How about you start a DIY about replacing and adjusting a hand brake? Than you can incorporate it into the whole brake job DIY.



And by the way, what rotors and pads did you end up buying, and from where?

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  #89  
Old 03-26-2008, 08:05 AM
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Quote:
How about a DIY about replacing and adjusting a hand brake? Than you can incorporate it into the whole brake job DIY
I'm not sure about "replacing" a hand brake (how many times does one do that?) but certainly adjusting the hand brake should be part of every rear rotor replacement. Of course, from the DIYs I read, most of you guys don't adjust the hand brake. You just put the rotors on.

Assuming the parking-brake drums have worn, all you lose is 30 thousandths of an inch (or so) in travel. So, in hind sight, I wish I had NOT taken the advice of the Bentleys and adjusted the parking brake myself. Now, for example, my parking brake locks up at the very first notch!
I'll have to adjust that in the cables and in the shoes; and you can bet I'll take pics of every step.

I first have the more important brake DIY to write up (if I ever get to it which I hope I do). Plus, at the moment, my major concern shifted to why the interior heating/cooling fan suddenly stopped working. I'm pretty sure it's related to the brake job. And, especially since I had a devil of a time getting the air-cleaner back together over the master cylinder ... I suspect there's a fan wire near there which is now kaput.

Do you know if the fan wires route near that horrid air-cleaner contraption?


Quote:
what rotors and pads did you end up buying, and from where?
I don't race. I don't drive erratically. I don't do twisties. I don't do anything that everyone else doesn't do ... so I went pure stock (I think you call that OE) using ATE rotors. Then I went OEM on the Jurid & Textar pads. BMW OEM on the sensors.

The only thing that isn't "stock" is the ATE Super Blue brake fluid which is waiting for the black label power bleeders and power extractors to arrive.

Do others agree that the brake sensor-to-harness connector should be the FIRST item put back (instead of the last) when doing the rear brakes?

Here is what the rear looked like when (almost) done; i.e., just before the last (damn) connection.

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  #90  
Old 03-26-2008, 08:40 AM
dvsgene dvsgene is offline
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Originally Posted by bluebee View Post
....at the moment, my major concern shifted to why the interior heating/cooling fan suddenly stopped working. I'm pretty sure it's related to the brake job. And, especially since I had a devil of a time getting the air-cleaner back together over the master cylinder ... I suspect there's a fan wire near there which is now kaput.

Do you know if the fan wires route near that horrid air-cleaner contraption?

Check your Final Stage Unit. May just be coincidental and not have anything to do with the brake job done.

For more information on FSU:

Final Stage Unit DIY sticky

If, in fact, it turns out to be the FSU, feel free to improve that DIY as well

Last edited by dvsgene; 03-26-2008 at 08:42 AM.
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  #91  
Old 03-26-2008, 07:22 PM
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What does the tangental cut in rotor edge indicate?

Thanks for the Final Stage Unit (FSU) "hedgehog" advice (aka porcupine resistor); I'll also look at the fuse deeply behind the glove box according to that article. My fan isn't "posessed" so much as it's just not working ... so I'm not sure if the FSU is the culprit but it seems a commonly failed part based on that article that it might be the cause of my fan stopping all of a sudden and not something I did when I cursed at that horrid air-cleaner box setup!

Back on topic for the BMW brakes DIY, can someone edify me as to why there is a "slit" in the side of the old and new rotors?

This slit seems, upon first glance, to be a wear limit grooved into a tangental slice of the rotor; but, the fact that my clearly worn (as measured by the "inchometer") front rotors still had much metal above the slice, makes me wonder.

Is the slice to indicate a horribly gone you're-gonna-die thickness of the rotor? If not, what does the rotor slice indicate?

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  #92  
Old 03-26-2008, 08:10 PM
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Quote:
Originally Posted by bluebee View Post
Thanks for the Final Stage Unit (FSU) "hedgehog" advice (aka porcupine resistor); I'll also look at the fuse deeply behind the glove box according to that article. My fan isn't "possessed" so much as it's just not working ... so I'm not sure if the FSU is the culprit but it seems a commonly failed part based on that article that it might be the cause of my fan stopping all of a sudden and not something I did when I cursed at that horrid air-cleaner box setup!
As far as I can remember, bad FSU causes the fan to be on Maximum Blow. (That's what I had.)


Quote:
Originally Posted by bluebee View Post
Back on topic for the BMW brakes DIY, can someone edify me as to why there is a "slit" in the side of the old and new rotors?

This slit seems, upon first glance, to be a wear limit grooved into a tangental slice of the rotor; but, the fact that my clearly worn (as measured by the "inchometer") front rotors still had much metal above the slice, makes me wonder.

Is the slice to indicate a horribly gone you're-gonna-die thickness of the rotor? If not, what does the rotor slice indicate?
This is the minimum thickness "groove" I referred to, earlier in this thread. And I agree, this is a "replace it now, or you're gonna die, you cheap bastard" kind of a limit.


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  #93  
Old 03-26-2008, 08:23 PM
dvsgene dvsgene is offline
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On a more related note. Since you are one of the few who has a micrometer. What is the measurement of a new rotor vs the old rotor? Just curious. How much was actually worn in your case. Assuming they were the same brand and can one still say average wear rate is .030 per set of pads?
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  #94  
Old 03-27-2008, 12:48 AM
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Every thousand miles wears off a thousandth of an inch or rear rotor

Quote:
What is the measurement of a new rotor vs the old rotor?
I was thinking the same thing!
I had not thought to check the new rotor thickness out until after I had the fronts on, but I did check the rear rotors before placing them on the axle (I'll do the fronts when my power bleeder arrives and I have to remove the wheels again).

While the Bentley manuals state the rear rotors start at ~20mm (0.787 inches), after a dozen checks, the new rear rotor measurements actually came out to 0.7800 to 0.7805 inches (amazingly they were all well within a half thousandth of each other).

Given my worn rear rotor was about 0.725 inches thick, that means in 60K miles, we wore off 0.780 - 0.725 = 55 thousandths of an inch (assuming the original rotor was the same starting thickness).

So, our actual measurements, for the rear (assuming this is the original rear rotor) jive with our assumption that there is a thousandth of an inch worn off the stock rear rotors for every thousand miles of driving.

Does about a thousandth of an inch of rear rotor for every thousand miles of driving jive with your results?

Do you get about 30K miles per set of rear pads?


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  #95  
Old 03-27-2008, 10:23 PM
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Is the wear limit for the parking brake shoes listed anywhere?

Is the wear limit for the parking brake shoes listed anywhere?

The Bentley shop manual that comes with the car simply lists the "pad" wear limit at 0.120 inch.It says nothing (that I saw) about the parking brake shoe wear limit.

For example, my parking brake shoe metal plate was almost exactly 0.1005 inches while the semicircular parking brake shoes (plate + pad) were uniformly 0.2375 inches so that leaves us with a pad thickness of 0.137 inches (without the shoe's backing plate).

Is 0.2375 inches (or is it 0.1370 inches?) within spec for the brake shoe friction material?

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  #96  
Old 03-27-2008, 10:32 PM
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Whatever the wear limit for the brake shoes, does it include the curved metal plate?

Whatever the brake shoe thickness limit is, does that brake material thickness limit include the curved metal plate (or is it just the friction material)?



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  #97  
Old 03-30-2008, 10:11 PM
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Beginning of "how I replaced my front & rear BMW E39 brakes, rotors, & sensors"

Since I'll probably never have the time to sit down long enough (many hours) to write the BMW E39 brake DIY to that I wish I had before I started, I think I'll just post, sporadically, some of my photos, so that someone happening upon this thread has all the answers in pictures that I was looking for, before they start...

I took over a thousand pictures of the complete job, some of which already are posted in the companion thread at
Bimmerfest > BMW Model Discussions > 5-Series > E39 >
What fluids (only) should be used in a typical E39 brake job?

http://www.bimmerfest.com/forums/showthread.php?t=266956

Future photos will be posted in the BMW brake bleeding DIY I'll write up when my Motive black-diamond pressure bleeder arrives (hopefully in better shape than my Motive power extractor did, as explained here)
Bimmerfest > BMW Model Discussions > 5-Series > E39 >
Brand new Motive Power Extractor does not work for E39 oil change

http://www.bimmerfest.com/forums/showthread.php?t=273813






Beginning of "How I replaced my front & rear BMW E39 brakes, rotors, & sensors" with the help of all you guys here.





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  #98  
Old 06-18-2008, 03:56 PM
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I think I have front brake pad deposition imprinting problems

Oh my, I never did sit down for the hours it would take to collate and annotate the hundreds of photos I took for the brake job ... but ... even worse ...

I now have the dreaded brake shudder (judder?) when slowing down at highway speeds using the front brake (doesn't happen when I pull up hard on the parking brake and the brake pedal doesn't seem to be vibrating ... just the steering wheel). The car doesn't pull to either side and I didn't hit anything ... well ... nothing that lived.

I'm reading about brake judder (shudder?) here and it seems that some people erroneously say rotors "warp" but the rest (like the Zeckhausen crew) affirm they generally do not warp - they highspot, particularly with the front vented rotors, as to warp would require the webs in between to deform.
http://www.stoptech.com/tech_info/wp...rakedisk.shtml

Apparently I now have uneven pad deposits caused by my pads pooping on my rotors. Probably from my poor braking technique (which I'm not even sure what that is). From reading, it seems the high spots overheat and create a really hard compound that doesn't wear as the rest of the rotor wears, leading to the vibration getting worse over time.

Serves me right for not following the brake pad bedding procedure exactly (I just went real fast and braked real hard a few times but never the 0.9Gs or so it takes for the ABS to kick in at 90mph or so).

Is there a way to 'rebed' the brake pads?

edit: luckily I re-found this BMW brake pad re-bedding procedure ... which I will try tonight (apparently at about 0.7Gs)
http://www.zeckhausen.com/bedding_in_brakes.htm

And there is a really good shudder/judder thread here ...
http://www.bimmerfest.com/forums/sho...=brake+shudder

Apparently, one "cure" is to rebed the pads to scrape the brake poop off the rotors; another cure would be to put really abrasive pads on the front calipers for a few days to scrape off the brake poop. I've learned the braking technique should be to stop hard, then let up, and not to leave the pedal down while rotors are hot.
http://www.zeckhausen.com/avoiding_brake_judder.htm

Last edited by bluebee; 06-18-2008 at 04:28 PM.
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  #99  
Old 06-18-2008, 05:42 PM
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If its brake pad deposition problems, you can rebed them, and it will help.

I know you said you notice this shimmy when you are braking, but did you notice it at all when you are just driving at certain speeds, and not braking? If so your thrust arm bushings may need to be checked out.
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Old 06-19-2008, 08:36 AM
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Quote:
Originally Posted by Mr Hyde View Post
you can rebed them, and it will help.
Last night, on my way home from work, I tried but there was just too much traffic, and, by the time I woke up in the morning, it was rush hour and on to work again. So, I didn't get a chance. Maybe I'll sneak out at 3am this weekend and do the dozen or so 90mph to 10mph stops to rebed the pads.

Quote:
but did you notice shimmy when you are just driving at certain speeds, and not braking? If so your thrust arm bushings may need to be checked out.
The shimmy/judder/shudder (whatever it's called) is only noticeable when I brake at highway speeds. The ride is smooth without shudder when driving at high or low speeds; and even braking at lower streetlight-level road speeds, has no shudder.

One thing I did notice is that the brake shudder/judder/shimmy/shaking is seeming to creep down to the lower speeds - so - I think - it's getting worse - meaning - I guess - I'd better do something about it now.

When I get a chance, I'll try to dial gauge it with all the lugs bolted and torqued to at least 40 foot pounds with a stack of washers on each of the five lug bolts holding the wheel on to determine if I can actually visually "see" the high spots. I might even buy a second dial gauge so I can do both sides at once to prove/disprove the 'warp' theory.
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