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If my clutch were to start slipping, would it slip more between 1st and 2nd, 2nd to 3rd, 3rd to 4th, 4th to 5th, etc under heavy acceleration.

The reason I ask: This past July while at Road Atlanta, the clutch began substantially slipping b/t 3rd and 4th while on the track and during a very hard run. I pulled the car in, let it cool down and took it out on the nearest road. Things were back to normal the rest of the day and pretty much since then. With 31k, it's probably safe to say it could be near the end of it's life. So, today I am driving it hard and I swear the car wasn't pulling like it should between 3rd and 4th, almost as if it were slipping. Any thoughts/advice on my original question?
TripleD
 

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tripleD said:
If my clutch were to start slipping, would it slip more between 1st and 2nd, 2nd to 3rd, 3rd to 4th, 4th to 5th, etc under heavy acceleration.

The reason I ask: This past July while at Road Atlanta, the clutch began substantially slipping b/t 3rd and 4th while on the track and during a very hard run. I pulled the car in, let it cool down and took it out on the nearest road. Things were back to normal the rest of the day and pretty much since then. With 31k, it's probably safe to say it could be near the end of it's life. So, today I am driving it hard and I swear the car wasn't pulling like it should between 3rd and 4th, almost as if it were slipping. Any thoughts/advice on my original question?
TripleD
That is the classic failure pattern for the E39 V8. Slip is noticed under severe duty and it seems to heal when rested for a while. It will worsen.
 

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Mine is on it's way out. Started slipping under load on the 3-4 shift. Now it's slipping in the 2-3 shift under heavy load. Daily driving it's fine. I'm holding on for dear life.
 

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Lscman said:
That is the classic failure pattern for the E39 V8. Slip is noticed under severe duty and it seems to heal when rested for a while. It will worsen.
Lscman, I was hoping you'd reply as you seem to have this game figured out. My real concern is that Barber is 2 1/2 hours from Atlanta. Should I risk the stock clutch at the track and not make it home, or scramble to order an aftermarket replacement? I can only imagine what a 2 1/2 hour tow bill would cost since I have a race shop here I trust.
Thanks for responding.
 

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tripleD said:
...I have a race shop here I trust.
Hey tripleD

The clutch on my Beast is also at the end of its life. :crying2: Must say, at 66K it didn't do too badly from what I read in the posts. My current option is to have BMW replace it with the OEM, since I don't track the car, and don't have the $4k+ to get the big dog version.

My concern is where to take it to have the job done. I have not had the best service & results from the BMW stealers here in Atlanta. And I have tried a few!

Any suggestions ( I noticed your mention of a race shop that you trust)?
Thanks!
 

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I've just gotten home from taking the car out and the same thing was happening to me - that and a bad smell.

I'm only at 13k miles on my 2003 and I am not happy with what is going on. I know I am going to have a tough time with the warranty on this one since they know that I track my car (only twice though).

Last time this happened and I took it in I couldn't reproduce the problem and the tech just told me it was "user error" - i.e. I was shifting at the wrong point.

Well, I am going to take it in next week and see what can be done!

SCORPIO
 

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SCORPIO said:
I'm only at 13k miles on my 2003 and I am not happy with what is going on. I know I am going to have a tough time with the warranty on this one since they know that I track my car (only twice though).

Last time this happened and I took it in I couldn't reproduce the problem and the tech just told me it was "user error" - i.e. I was shifting at the wrong point.
While it is a true statement that the vast majority of the E39 M5 clutch maladies can be attributed to 'operator error/abuse' that is NO reason for SA's SM's and Techs to paint everyone with the same brush. I, too, was told at the time that "every single E39 M5 clutch failure has been due to operator error" by an arrogant pr!ck of an employee of BMWNA.

FWIW, the BMWNA Uber-Regional Tech Rep took my car out for a drive when I complained of occasional slippage, and reported back "unable to duplicate symptoms." I then took my Beast to an independent shop I trusted, grabbed a tech off the floor, and had him try to recreate slippage with me in the passenger seat. He did. (There is a sure-fire way to determine if your clutch is slipping, but it is a DESTRUCTIVE test. I'd recommend against it unless you're prepared to R&R the clutch in question at the same time.

Bottom line: when they disassembled my clutch, they found (1) normal wear for 43K miles, but NO signs of abuse, and plenty of friction surface remaining, and (2) a failed Self-Adjusting Mechanism. As such, my clutch was replaced under the 4/50K warranty at no cost to me. And no apology from the arrogant regional tech rep.

FWIW(2), I tracked my car, and my dealer knew so. I've had them do brake fluid flushes when I was unable to fit one into my weekend wrenching schedule. The fact that you participate in Driver Education events should have ZERO bearing on clutch replacement under Full Maintenance Protection Plan, or the bumper-to-bumper warranty, if it's a failed component. That's merely the copout of a spineless SA, or a dealership that prefers customer $$ over BMWNA warranty credits.

TripleD, if I were considering a clutch replacement on my own dime, I would most likely go for the Sachs Performance Engineering ('race' clutch) setup with the factory (LuK) dual-mass flywheel, much like Dick (RRoberts) and One-Lap Meistro Roy Hopkins (ROH) have done. While the UUC upgrade is indeed bulletproof, I still cannot justify 2X the cost of the Sachs/OE replacement....

As for the best shop in 404 to do the work, I'm at a loss. I would probably take the aftermarket parts to Nalley/Chris BMW and have them do the install. They've done such great work for me in my nearly five years of ownership, that I would not hesitate to use them for high performance stuff. If you recall, their Master Tech Tim is the one who built the E39 M5 Touring that was featured here on the board a few years back...

Good luck!
-Dave
 

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It may be difficult to "prove" that a self-adjusting mechanism is not functioning properly, unless the clutch pedal height goes south (with no other defect) or broken parts are literally rattling around inside the pressure plate or bell housing. The condition of the pressure plate mechanism can not be accurately assessed without an autopsy. Fact is, nobody is going to dissect a pressure plate to confirm the condition of the SAC. They are not designed to be dissassembled. Only a clutch component remanufacturer will tackle one.

You are at the mercy of the mechanic to "declare" a root cause of failure that is covered under warranty. Suggesting the SAC has failed is always a good practice for an E39 owner. SAC failure will invariably lead to clutch wearout & miles is irrelevant.

Fact is, an expert mechanic will seldom be able to determine whether a cooked flywheel and worn out clutch disc was caused by 1) a bad SAC or 2) abuse or 3) normal lifecycle wearout. The only time an accurate assessment can be made is when the SAC is totally broken/malfunctioning.
 

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Teutonaddict said:
TripleD, if I were considering a clutch replacement on my own dime, I would most likely go for the Sachs Performance Engineering ('race' clutch) setup with the factory (LuK) dual-mass flywheel, much like Dick (RRoberts) and One-Lap Meistro Roy Hopkins (ROH) have done. While the UUC upgrade is indeed bulletproof, I still cannot justify 2X the cost of the Sachs/OE replacement....
Well, if you're going to start doing some math...

The Sachs Race clutch for the E46 (which you have to modify your E39 flywheel to accept) costs around $1350 last time I checked. Hopefully you'll get the mileage out of it that one would expect for a well-designed pressure plate using a 240mm clutch in an E39. How that "race" material works long-term in street driving (more deliberate slippage than in track use) remains to be seen. With the machining of the E39 flywheel at a conservative $200 labor cost and the $100 larger slave cylinder you need, you're at $1650.

Total UUC flywheel/clutch kit cost comes to $2750.

$1100 difference so far, right?

The OE BMW 850CSi clutch as used in the UUC kit retails for around $850, and has years of proven reliability in the 400hp/4,000lb 850CSi. So your cost differential gets cut in half at your next clutch change... and that's not taking into account whether the 240mm Sachs Race clutch will last as long as the larger 280mm 850CSi clutch, which would even skew the value ($/mile) even further.

We haven't even discussed the fact that dual-mass flywheels are considered consummable items. The built-in dual-mass mechanism will break eventually. In lower-powered cars, I have not seen a dual-mass flywheel last through the third clutch change. Many techs recommend replacing the OE dual-mass flywheel at each clutch change, to the tune of $600 for the M5.

If you need to (or simply do because you should) install a new dual-mass flywheel with the Race clutch at the next clutch change ($600 + $200 machining = $800), you've spent just about the same as you would with the "more expensive" UUC setup. The single-mass UUC flywheel never needs replacing (other than the $70 friction surface every 3-6 clutch changes). In fact, the UUC flywheel has a lifetime warranty.

Sometimes spending more up front actually is the better value.
 

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I did some research on M5 clutches and the SPEC stage 3, 9.5" billet plate clutch kit

(#sbd633) with the lightened dual mass flywheel (#sb63dml) is the best setup with no rattling

noise....all for $1268+install....no dealers but SPEC directly carries this model
 

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IIRC, a few board members have had trouble with the spec clutch, so you may want to look around for more info. I believe www.beastpower.com sells the spec clutches.

I also don't know if i'd say the best clutch would be a 240mm unit when a 280mm unit is available. As you may know from porsche ownership, a dual mass flywheel will eventually fail. I think these are reasons many on this board go with the uuc clutch, and it's what i'll do when my clutch fails.
Just another opinion...
Mike

marcvip said:
I did some research on M5 clutches and the SPEC stage 3, 9.5" billet plate clutch kit

(#sbd633) with the lightened dual mass flywheel (#sb63dml) is the best setup with no rattling

noise....all for $1268+install....no dealers but SPEC directly carries this model
 

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Certainly this flywheel is cheaper than the Dinan flywheel an it looks like a quality piece. I'd like to know if that flywheel mates up to the stock clutch. Might be an economical solution?
 

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boostmiser said:
Certainly this flywheel is cheaper than the Dinan flywheel an it looks like a quality piece. I'd like to know if that flywheel mates up to the stock clutch. Might be an economical solution?
Isn't it also a bit less expensive than the uuc model?
Mike
 

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mottati said:
Isn't it also a bit less expensive than the uuc model?
Mike
Yes, but the UUC flywheel is a larger diameter than stock...which is why many say to buy it. It can handle a larger load more efficiently. But I personally don't think I need all that...not to mention I can't afford it. The Dinan is a machined, same diameter as stock flywheel for mucho dinero.

Dinan = $2,000
"The factory Dual-Mass flywheels have been lightened by 7 lbs. for an 18% reduction in overall weight and a 40% reduction of rotational mass. The lighter flywheel provides for faster engine revs and acceleration, as well as a dramatic improvement in throttle response. The enhanced performance is provided without compromising the durability and smooth engagement that you would expect of a 5 Series BMW clutch."

Rogue = $589
CNC machined to factory dimensions for a exact fit
Replaceable, hardened steel friction surface
Helicoil inserts for pressure plate bolts (prevents bolts from stripping)
Enlarged dowel hole, like factory flywheel (where applicable)
Flywheel gaul plate and replacement 10.9 flywheel bolts
Replacement pressure plate bolts
Completely zero balanced
Weight savings: 14 lbs. (525i, 528i, 530i)
Weight savings: 24 lbs. (540i)
Weight savings: 27 lbs. (M5)
Manufactured to Rogue Engineering specifications, to accept our patented semi-metallic backed sprung hub disc
 

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My only concern is the Rogue unit is for all e39's. I'm a little skeptical of a flywheel that will work on a 525 and an M5.
Mike
 

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the other thing is the weight. See above (I edited my link). It's 27lbs lighter than stock whereas the Dinan is 7lbs. That's a big difference which may result in some adverse effects...but I really don't know what they may be.
 

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Guys,

I have also done some research in this area as I am building up an S2. Just had the headers done and what a difference. Still have the stock clutch currently.

The Dinan flywheel is still dual mass less 7lbs. The OEM clutch gets mated to it. The dual mass unit will dampen all vibrations. Rember the OEM clutch is NOT sprung hub. Supposedly Dinan will be releasing a special clutch that has been tested in their S3 offering. It most likely will be 240mm.

The UUC setup with the 850csi clutch is single mass with a sprung hub clutch. The sprung hub clutch provides the dampening via the springs embedded in the clutch disc. It does not provide the same noise dampening that the dual mass flywheel does and therefore you will be subject to some chatter at idle.

The Rouge is single mass and if you pair up the OEM clutch, the noise would be just too much to tolerate. Rouge is supposedley going to come out with a clutch soon as Ben now has an E39 M5 that he is playing with.

SPEC clutch/flywheel setups are similar to UUC but in 240mm diameters. I have only read negative reports about their products and support on this board.

Hope this helps.
 

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I've read the SPEC negative feedback here and realized it was due to a poor installation.....most likely due to replacing the clutch without resurfacing the stock flywheel..

If you research SPEC as a company they are very well established in the Racing industry for many years....the clutch setup I will install from SPEC is used in Grand Am Cup cars....and is not available at beastpower.com........I want a lightened dual mass flywheel to avoid rattling noise.....UUC clutch is heavier and in this setup size is not important.......also UUC is double the price$$
 
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