Did anybody change the DCT clutch?

[RomanK]

Did anybody change the DCT clutch?

I need to know, are there any other reasons to change the clutch besides
friction of the clutch under WOT?

I have the issue but I don't know what I should change to fix it.

I feel some bumps from my rear subframe when I touch my accelerator after the engine bracking (when I applicate / release the throttle on the high speed)... But I have the solid subframe and diffirential bushings... So it is backlash in a driveline.

I thought that my half-axels are damaged, because I feel some backlash manually. I changed the right half-axel, but it did not have any influense on my issue. And backlash in half-axel was really small. So I do not see any reasons to change the left half-axel.

I want to know, can the clutch of DCT to has some influence to this bump or not... I really don't know how can I fix it. Please, help.

[SYT_Shadow]

Is your engine supercharged?

I haven't heard of anyone blowing the clutches unless they are supercharged.

Two companies, SSP and Dodson I think sell aftermarket clutches but there isn't that much information out there about them


Edit: have you checked your guibo? That's the rubber flex disc between the DCT and the driveshaft. It could be old and destroyed

[RomanK]

Originally Posted by SYT_Shadow

Is your engine supercharged?

I haven't heard of anyone blowing the clutches unless they are supercharged.

Two companies, SSP and Dodson I think sell aftermarket clutches but there isn't that much information out there about them


Edit: have you checked your guibo? That's the rubber flex disc between the DCT and the driveshaft. It could be old and destroyed

My car is full standart. Only acrapovic exhaust. 130k km for now..

I checked my guibo, but it looks like normal without any damages. Moreover, I feel this bug already 20-30k km... so i think it would be destroed a lot of time earlier...

[SYT_Shadow]

Originally Posted by RomanK

My car is full standart. Only acrapovic exhaust. 130k km for now..

I checked my guibo, but it looks like normal without any damages. Moreover, I feel this bug already 20-30k km... so i think it would be destroed a lot of time earlier...

I think it would be very difficult to break a DCT in 130k km. I'm sure it's possible, but unlikely.

The rubber flex disc sometimes looks fine, but if yours has that many km it's cracking for sure. It's cheap, I would start there

[RomanK]

As for the DCT clutch slipping I fully understand. I am not so nuvice in technic. My DCT clutch does not slipping, I am sure. I thought that some driveline backlash can be inside... for example double mass flywheel or something else in clutch.

Engine and trans mounts are good.
Drive shaft rear universal joint has a little backlash, but it is not so significant I guess.
I had the small backlash in right half axel. I changed it and noticed some small improvements in the driving of my car, but it did not solve the main problem.
Drive shaft center coupling body mount is good.
Rear subframe bushings is solid aluminium. And diff mounts are delrin. The problem was with factory bushings and after the changing to solid it is there as well. So, subframe and diff bushings does not have any influence on my issue.

The good version about guibo. It looks good, but maybe it is too soft?

Thank you for your comments.

[Mit_Boost]

Forget how, but isn't there somehow you can reset the DCT adaptations? Maybe it'll clean itself up

[RomanK]

Guys... Yesterday I was on the lift and diagnose my rear susension. I noticed a lot of small backlashes in my suspension joint. I didn't hear any bumps on bad roads, really suprized me this.

I will change 6 suspension arms and will write here, will there transmission bumps after that or not...

I really suprized... really hope that it will fix my problem.

[dparm]

Originally Posted by Mit_Boost

Forget how, but isn't there somehow you can reset the DCT adaptations? Maybe it'll clean itself up

Unlike the SMGs, the M-DCTs are "self-adjusting" and should never need it unless they are replaced or receive new internals. You can still force the adaptation process with the BMW diagnostic computers.

[RomanK]

Hello Guys...

Need help to fix my problem. Don't know what to do next.

I still have the problem described above.
I changed right half-axel, rubber flex disc, constant-velocity universal ball joint...

Today I tried to find my problem again:

I pressed a brake and accelerate my car. And I see the backlash in input flange of my diff. Is this a problem and how to fix it?

[RomanK]

Originally Posted by DrFerry

The OEM M3 rear differential limited slip unit is a GKN Visco-Lok part which uses a fluid in between shear plates to provide a limited slip effect. Unfortunately it does wear out. The drive shaft flange movement I see in the video is probably a combination of worn Visco-Lok limited slip unit and a worn ring and pinion causing backlash. See this thread for more information. I replaced mine with a Quaife torsen type limited slip diff unit due to the "clunk".

http://www.m3post.com/forums/showthread.php?t=788992

Thank you for your post.
I should tell you that my diff has 50k miliage on highway generally... The Visco-Lok works great, I feel it.

Are you sure that on the video my diff is not so good? Are you sure that such clunk is not normal?

May be it is just splines of input flange?

[Sneaky Pete]

Just as a fyi...replacement clutch packs are available from BMW for the DCT.

[OM VT3]

Originally Posted by Sneaky Pete

Just as a fyi...replacement clutch packs are available from BMW for the DCT.

Better off going aftermarket replacement is a rip off

[Sneaky Pete]

Originally Posted by OM VT3

Better off going aftermarket replacement is a rip off

How much is the aftermarket cost?

[BanjoPaterson]

Originally Posted by Sneaky Pete

Just as a fyi...replacement clutch packs are available from BMW for the DCT.

Do you have the part number or any links?

Thank you ☺️

[BanjoPaterson]

Originally Posted by BanjoPaterson

Do you have the part number or any links?

Thank you ☺️

My bad. Just found it 28407842841

[OM VT3]

Originally Posted by Sneaky Pete

How much is the aftermarket cost?

Just something like oe about 2k OEM is like 4k

[roastbeef]

have you taken off the heat shields above the xpipe and inspected the flex disk and center cv joint? we have two cv joints on our driveshafts... you can't see the flex disk or middle cv joint without taking off the xpipe and heat shields. it is a big job. easy, but time consuming.

[Sneaky Pete]

Originally Posted by OM VT3

Just something like oe about 2k OEM is like 4k

I though OEM was around $2300?

[RomanK]

Originally Posted by roastbeef

have you taken off the heat shields above the xpipe and inspected the flex disk and center cv joint? we have two cv joints on our driveshafts... you can't see the flex disk or middle cv joint without taking off the xpipe and heat shields. it is a big job. easy, but time consuming.

It is not a problem for me at all.

I already changed right half-axel, rubber flex disc, constant-velocity universal ball joint...

Today I took off my diff and showed it to the master of diffs... It tells me that all is ok with my diff.

I see the last point here... I should check the splines of my driveshaft... Don't know what else can have infuence on my clunk.

[RomanK]

Originally Posted by DrFerry

Are you sure that on the video my diff is not so good? Answer = No. I am not certain, because I have not driven the car or inspected it, but I think it could be. I am giving you only my opinion based upon the video that the Limited Slip unit maybe worn inside the differential casing (see operating principle section in the image below). However, ALSO see the image screen capture below where others had a similar clunk and it turned out to be the driveshaft (center coupling).

Are you sure that such clunk is not normal? Answer = The clunk is not normal. Search the forums for the word "clunk". The E90 series M3 does is not designed to "clunk". Though over time, many do seem to develop the condition either due to the driveshaft center bearing or the limited slip diff unit and/or ring and pinion gear backlash..

May be it is just splines of input flange? Answer = The amount of rotation of the driveshaft lash (~20 to 30 degrees) seems too large to me to be just caused only by the driveshaft input shaft splines. Again, that's my opinion. However, some forum members have fixed 'the clunk' by replacing the driveshaft because the driveshaft center coupling was worn or damaged.

See the attached .pdf GKN Visco-Lok technical document at the end of this post showing the fluid shear plates - as well as a posting image screen shot AND then search the forums some more. I am just trying to help.

_

Thank you for your post... Will research it...

[GORDON.M3]

If you have a good connect at a dealer you should reach out to them.
A local dealer of mine quoted me $1400 installed for new clutches. VERY reasonable.
But my M3 only has 50,000Km right now, so nothing is needed except repairing that damn'd seeping ECU gasket.

[RomanK]

Yesterday I tried another M3. I noticed that the kick when I push the accelerator on 140-150 kmh is noticed too... But without clunk. On my car I hear clunk on the left rear. I thought that it is my left half axel, but manually I can't find the backlash there.

So the kick i think it is normal (i think it is dual mass flywheel), but the clunk sound heared on my car on the rear it is not normal.

One more question.

On another M3 i tested yesterday I noticed very smooth downshiftings on the drive mode on small speeds (3-2-1 gears). So my shiftings on my car 3-2, or 2-1 more hard. I think it can be connected with deterioration of my clutch. Is there some function adaptation of the clutch in Rheingold? I mean maybe I can do an adaptation of it to make my downshiftings in drive mode more smooth? Is such function somewhere? I think on my car first owner made a lot of launches, so my clutch is not so good for now. But I am not noticing any clutch slipping now...