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Discussion Starter · #1 ·
I went to change the brake pads in my 2000 this morning, the front right caliper is totally shot. The outer seal was not mounted in the groove in the caliper and as a result the piston is pretty badly corroded. I had a re-build kit on hand (same P/N as for an E36 M3) and was going that route, but there's no hope since the piston is so badly corroded.

None of my local dealers have a caliper in stock and the piston isn't available separately according to the dealer so I ordered one, it'll be in on Monday, list price is $381.

Check your outer seals when you change brakepads...

Regards
 

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I understand this may not help you from a time line schedule, but you should check the classifieds for someone who may have parts left over from a big brake kit upgrade. I *think* i may still have calipers from the front of my M5.

I'd have to search thru some garage/shed stuff to be certain, as i can't remember if I'd already sold them. Unfortunately, i'm nowhere near you so you'll likely have a new caliper from you dealer much faster.
Mike
 

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mottati said:
I understand this may not help you from a time line schedule, but you should check the classifieds for someone who may have parts left over from a big brake kit upgrade.
I do still have my OE calipers from my StopTech upgrade, so if Mike sold his and you're at all interested, shoot me a PM.

-Dave
 

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Discussion Starter · #4 ·
Thanks for the offer guys, but I am going to go with a freshly rebuilt one from the dealer.
 

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Yowch! Maybe we should all be changing our pads more often so the caliper pistons never get extended so far!
 

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Discussion Starter · #6 ·
Need4Spd said:
Yowch! Maybe we should all be changing our pads more often so the caliper pistons never get extended so far!
I think that they are the original stock pads, the car has 58K miles, original brake fluid too by the look of things. The pads have about 3mm left on them pretty much all round. The rotors look good although I haven't measured them. Last week during my commute after I had been stuck in heavy traffic for about an hour they felt like they were grabbing very slightly, but when I came out of work at lunch they were fine again. The amount and severity of the corrosion on the piston suggests that the outer seal has been loose for some time.

I have a new set of Hawk HPS installed on the other three wheels and some HP Plus just in case I decide to do a DE with it.

The caliper will be in on Wednesday I am told now, so I have a little work to do on Wednesday night since I am going skiing for a week next Saturday.
 

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jhowton said:
I think that they are the original stock pads, the car has 58K miles, original brake fluid too by the look of things.
I thought change of brake fluid was part of Inspection I??
Regards,
Jerry
 

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Discussion Starter · #8 ·
gsfent said:
I thought change of brake fluid was part of Inspection I??
Regards,
Jerry
Actually no, Inspection I contains the line:

"Check level of brake/clutch fluid in reservoir. Add fluid if required."

Inspection II adds:

"Brake Fluid Service (Replace brake fluid every 2 years (time interval begins from the vehicles production date)"

I have only owned the car since December so I am unsure as to what has been done already.

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I think that they are the original stock pads, the car has 58K miles, original brake fluid too by the look of things. The pads have about 3mm left on them pretty much all round.
Yeah, that would be pretty extended, alright. But from the looks of it, you can't really avoid outer corrosion by replacing the pads or else you'll be doing that every 5k.
 

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jhowton said:
Actually no, Inspection I contains the line:

"Check level of brake/clutch fluid in reservoir. Add fluid if required."

Inspection II adds:

"Brake Fluid Service (Replace brake fluid every 2 years (time interval begins from the vehicles production date)"

I have only owned the car since December so I am unsure as to what has been done already.

Regards
Thanks, but I am a little confused. Inspection II says replace every two years from producton date, but Inspection I will come up in two years or so for most of us, Inspection II will be a lot later. So it seems it needs to be replaced/flushed every 2 years from production date. Accordingly, it would seem it would need to be done on Inspectin I for most of us.
Regards,
Jerry
 

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Accordingly, it would seem it would need to be done on Inspectin I for most of us.
Agreed. It's 2 years regardless. It has more to do with the time that moisture in the air can have a chance to react with and combine with the fluid than miles. Even if it's only "Inspection I" time, I'd still insist (and pay for if need be, if you're off the maintenance plan) on a fluid flush if it's been 2 years since the last one.
 

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Need4Spd said:
Agreed. It's 2 years regardless. It has more to do with the time that moisture in the air can have a chance to react with and combine with the fluid than miles. Even if it's only "Inspection I" time, I'd still insist (and pay for if need be, if you're off the maintenance plan) on a fluid flush if it's been 2 years since the last one.
Mine was done, I even supplied the Superblue!!
Regards,
Jerry
 

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jhowton said:
I have a new set of Hawk HPS installed on the other three wheels and some HP Plus just in case I decide to do a DE with it.
Hawk HP Plus pads are not appropriate for a high speed driving event! The friction calls off a cliff when you exceed the maximum operating temperature (MOT) of these pads, just like the Hawk HPS, only slightly higher. You can have strong brakes one lap and then have nothing the next lap. No warning, no gradual onset of fade. Just you and whatever runoff you have at the end of the braking zone. :eek:

Lest you doubt my word, I was warned by Rob Nelson, former President of the Hawk Friction Division, to never allow a customer to track with the HPS or HP Plus. The HP Plus is an ideal autocross pad, with incredible cold bite and a very high friction level. But its behavior as it approaches MOT makes it a very poor choice for the track. You really should try the Hawk HT10 instead.
 

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Discussion Starter · #14 ·
DZeckhausen said:
Hawk HP Plus pads are not appropriate for a high speed driving event<SNIP>
Thanks for the warning Dave. I have been using HP Plus on my M3 for track events, maybe I am just not using the brakes enough. You are right, when they get very hot they do stop working quickly but just easing up on them a little allows them to cool off enough to come back. I mostly drive at Road America, Blackhawk Farms and Gingerman and I still drive on street tires (maybe that has something to do with it) and they seem to be OK for 20 minute or so sessions. I think I'll try some HT10s instead for the next Road America outing in April though, it is a little bit "exciting" when your brakes fade.

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DZeckhausen said:
Hawk HP Plus pads are not appropriate for a high speed driving event!

Lest you doubt my word, I was warned by Rob Nelson, former President of the Hawk Friction Division, to never allow a customer to track with the HPS or HP Plus. The HP Plus is an ideal autocross pad, with incredible cold bite and a very high friction level. But its behavior as it approaches MOT makes it a very poor choice for the track. You really should try the Hawk HT10 instead.
Dave
Interesting. I have used HP Plus on my 3800# Audi quattro at the track with very good results. They do not have as much braking as Hawk Blues, but I was pleasantly surprised. The rears do tend to squeal a little, but I found I could use them on the street also (during my lazy period! hiha ). Oh, and I push the car, it runs in the instructor group. Just my experience.
Regards,
Jerry
 

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jhowton said:
Thanks for the warning Dave. I have been using HP Plus on my M3 for track events, maybe I am just not using the brakes enough. You are right, when they get very hot they do stop working quickly but just easing up on them a little allows them to cool off enough to come back. I mostly drive at Road America, Blackhawk Farms and Gingerman and I still drive on street tires (maybe that has something to do with it) and they seem to be OK for 20 minute or so sessions. I think I'll try some HT10s instead for the next Road America outing in April though, it is a little bit "exciting" when your brakes fade.
If you're running the M3 at Road America, you should try out the Performance Friction 01 (PFC01) pads instead. They don't make them to fit the M5, otherwise I would have suggested them first. Didn't realize you were running a different car at the track.
 
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