Am I replacing the clutch, master or slave?

[MinimumJargon]

So just finished replacing rear shocks and front wheel bearings.

On to problem #3 of 5 which I need a little help figuring out.
This is a bone stock 2012 MS3 with 155000 miles
I replaced the trans fluid with redline about 20000miles ago.

About two months ago when I would accelerate quickly to around 4,5rpm and higher the next time I would push in the clutch it would be noticeable stiffer, after that it goes back to feeling normal. Didn't effect shift at all.

Last week though I went on a two hour drive, now I'm having trouble getting into all gears.
no grinding below 3000rpms just real notchy feeling waiting for the synchro to sync, above 3000rpms is now impossible.

It feels like I'm not experiencing any loss of power. I can still do a smooth pull when I'm in gear, clutch doesn't feel like it slips, RPMs stay smooth and engages normal.
The pedal is still stiffening after acceleration.
No visible leaks
Reservoir is full

I picked the car up at 100000miles and am unsure if the clutch has ever been replaced.

I want to say it's a hydraulic issue the way the pedals acting.
Though I'm preparing myself to swap this clutch. Is there an inspection plate?


Anyone got any insight?

Thanks, JR

[Fstrnyou]

When I had a funny pedal feel after high revving, it was an issue with the ToB.

[MinimumJargon]

Originally Posted by Fstrnyou When I had a funny pedal feel after high revving, it was an issue with the ToB.

Never had a bad throw out bearing before but your right seems like some of the symptoms fit.

I dont have any of the noises though.
Did you have any vibration at idle or noises when it went bad?

[SyntheticAtmosphere]

I too had a TOB going and was getting locked out of gear after higher RPMs, car otherwise drove fine. Once I separated the eng/trans, the bearing would rattle when I spun it. I think I caught it before it would cause damage to the input shaft like a few people here have found. At the same time I also went with a Fidanza/Luk combo because the OEM DM was running right on the line of being out of spec. The bad TOB issue also was causing the friction disk to wear uneven. Its a labor intensive job, but can be done with a good selection of regular hand tools.

[Fstrnyou]

Most commonly after a 4th gear log or any high rpm activity, the clutch pedal would stick to the floor. I'd have to pull it up and then pump it to loosen it up again. I drove it like that for quite a while since normal driving didn't cause any issues. Eventually my clutch disk friction material separated during some "spirited" driving...somehow. When I pulled the trans to replace the clutch, the ToB was in 2 pieces. I didn't have any vibrations until the disk broke. I drove it home with the broken disk, but shifts were difficult, especially downshifting.

[phate]

Agreed on potential ToB issue - Clutch Issues - Harder to press as I rip through the gears

Check that you have sufficient travel at the slave, though. You should get ~3/4" travel of the piston. If not, it is a hydraulic issue with either the master or slave.

YouTube Short

YouTube Short

[MinimumJargon]

Originally Posted by phate Agreed on potential ToB issue - Clutch Issues - Harder to press as I rip through the gears Check that you have sufficient travel at the slave, though. You should get ~3/4" travel of the piston. If not, it is a hydraulic issue with either the master or slave. http://youtu.be/xy3rT9zVnU4

Awesome thanks for this I was looking for a measurement for the throw of the slave 👍.

After now seeing all the info on ToB for these cars though I feel that's the issue but, I can hope it's still hydraulic right

Been doing some research on the DMF as well, I think that is the cause of my cars vibration issue as everything else has checked out fine. I think its failing and cause the ToB to degrade.

Looked over the how to here for a clutch swap. Doesn't seem to bad just not to excited about doing it.

Is the cheapest clutch as flywheel combo really the luk and fidanza SMF?


JR

[Fstrnyou]

I would strongly consider evaluating your long term plans with this car before pulling the trigger on a clutch.

Although, considering what's sitting in your stable, making the MS3 fast is a bit of a waste. That being the case, the LuK/Fidanza is probably you best option.

[MinimumJargon]

Originally Posted by Fstrnyou I would strongly consider evaluating your long term plans with this car before pulling the trigger on a clutch. Although, considering what's sitting in your stable, making the MS3 fast is a bit of a waste. That being the case, the LuK/Fidanza is probably you best option.

Yes, I'm not planning on increasing the hp at all. At most I'll do full suspension.

My worry is if I ever have to sale the car I'm going to have to explain all this clutch chatter for going SMF.

Trying to decide if I need to plan for that and spend more or just get it done and say "because racecar"

[SyntheticAtmosphere]

Yes, the DMF is rich, and not worth reusing.

[MinimumJargon]

Ok... update

Just got my new luk clutch installed w/ fidanza flywheel... out of 5 clutches I've replaced it gets my biggest middle finger. But it's done.

The vibration is gone 100% WOOT!, pretty sure the DMF was to blame it had so much slop and didnt look centered.
Pressure plate was down 1.125mm in thickness.

Got it all back together annnd it wont go into gear when the car is running, feels like it's not fully disengaging... *kill me now*

Pressure plate was installed the correct direction everything was torque to spec.

Going to re-bleed the slave tomorrow and check the throw on the slave. I know its moving but not sure how much.

Thinking maybe the master cylinder gasket is leaking fluid by. Only thing I can think of the makes sense.
Might try a leak down to.


Thoughts?


Bonus: Video of how much play was in the DMF.

[Thor Hammer]

Originally Posted by MinimumJargon Ok... update Just got my new luk clutch installed w/ fidanza flywheel... out of 5 clutches I've replaced it gets my biggest middle finger. But it's done. The vibration is gone 100% WOOT!, pretty sure the DMF was to blame it had so much slop and didnt look centered. Pressure plate was down 1.125mm in thickness. Got it all back together annnd it wont go into gear when the car is running, feels like it's not fully disengaging... *kill me now* Pressure plate was installed the correct direction everything was torque to spec. Going to re-bleed the slave tomorrow and check the throw on the slave. I know its moving but not sure how much. Thinking maybe the master cylinder gasket is leaking fluid by. Only thing I can think of the makes sense. Might try a leak down to. Thoughts? Bonus: Video of how much play was in the DMF.

Possible clutch disc stuck to pressure plate. its happened before. Search for that post on here.

Also, did you replace the master or slave recently? Is the slave piston moving?

[MinimumJargon]

I have not opened or replaced slave or master cylinder. Measured the throw of the slave it's just over 1/2" not 3/4". Removed the boot on the slave it has no leaks. Removed the master cylinder and got an OEM one from the dealer arriving tomorrow. Just another 130$...

I'll look for the stuck pressure plate thread, thanks for the info. I did put it in gear, then turned it on and moved it around a little already. It's not killing over, you can feel a small tug with the pedal in like it's not all the way disengaged so it's not 100% stuck.

[SyntheticAtmosphere]

I had a cracked clutch pedal bracket, which I think was the root of my clutch issues. Once I had replaced everything I had an issue with the slave travel not being enough to fully disengage the clutch. Had to remove the clutch pedal assembly to find the crack, couldnt see it while lying under the dash. Another symptom, the pedal would periodically stay at the floor, especially while bleeding the system.

[MinimumJargon]

Well I got the new master cylinder in and bled the crap out of the line. I didn't really notice an increase in throw from the slave but maybe all it needed was that extra 1/16th or so to fully disconnect the clutch. Or maybe I swapped it for no reason and just needed to smash the crap out of the pedal a few dozen more times to break in the clutch springs.

Ah well, seems fixed. Took her for a drive, all the vibration and noise is gone, it's so nice driving it again.

Oddly I am not experiencing any of the aforementioned clutch chatter with the new flywheel, AC on or off. It's just as quiet as stock which I'm quite happy about. How free flowing RPMs are might take a little getting used to. Push in the clutch and the RPMs jump up instead of dragged down. Feels like it wants to go go go.
Definitely way way easier to heal tow now.

I did take apart the old clutch master cylinder. It did feel a little loser then the new one but I saw no visual wear or damage.

Thanks for all the help and input guys,
JR

[Frequentflyer]

Rather than start a new thread I will piggyback off this one and bring it up top. The temperature was in the 40's this AM and all of a sudden my clutch pedal feels odd. Seems real loose in the first 3-4" of travel and then firms up. It also feels like it engages a bit lower than it used to within about 2" of the floor. In fact, I almost stalled the car this morning in first gear because of it. I drove about 25 miles and it didn't get any worse or better. I didn't have time to check fluid levels and for leaks because my wife and I were headed to the airport. I've got almost 221,000 miles on the car ('08); original clutch so considering some dudes have replaced their slave cylinders multiple times, I think I'm due (and lucky). I don't have problems getting it in or out of gear yet, although I have noticed more upshift grinds in higher gears possibly due to the slave cylinder being sluggish.

I just ordered the latest version of the part and a Clutch Master braided line. Hopefully it fixes my issues. Anyone have experience with the braided line instead of the OEM hardline?