clutch shudder (6MT)

I'm thinking this is a regular maintenance item, but I definitely spoke too soon when it came to "no problems" w/ my car. Anyway, here is the meat from that post. (BTW, I've driven MT for years, and never had a clutch take a dump on me in so few miles - 62K). Picked up my buddy from BMW dealer this morning (ironically, right next to P-car dealer), and on the way into work, my car started acting up. I'm researching it here, but I welcome any/all input. I was shifting from 3rd to 4th (normal driving) and I couldn't readily put it into 4th gear. I put it in neutral and released the clutch, then clutch in and semi-muscled it into 4th. I'm thinking "that was strange". Then I go to downshift, and 3rd is tough to engage. Again, I semi-muscle it. I had about 2 miles to the office, and I repeated the process using 2nd, 3rd and 4th. I couldn't get it into 1st at a stop light, so I started in 2nd. anyway, in the work parking lot, w/ the engine running I couldn't put it in any gears fully. reverse would kinda take, but not fully "locked in". When I turned the motor off, the gears felt fine. The clutch pedal feel has definitely changed (lighter and higher pickup and shuddering as I bring it up to engage the transmission with the motor). History: I put in a short shifter 3+ years ago and got the console cable ends aligned correctly. about a month ago I swapped transaxle fluid (3 Liters) for Royal Purple 75W90. It may be 2 ounces short, but I haven't experienced any issues in 1500+ miles of normal driving. I am right at the 2 year mark for replacing brake/clutch slave cylinder fluid, which I've done twice in the 4 years I've owned the car. 1) I don't think the friction material on the clutch is toast or the flywheel surface 2) I've checked the shifter cables, they're good, and still in their proper positions. 3) I checked for brake/clutch fluid leaks. None, and bled the clutch slave. 4) maybe a pressure plate spring? 5) maybe a crapped out dual mass flywheel? Curious as to why would the gears "go in" w/ the motor stopped but not when running? I got the car home and am going to raise it and start taking it all apart tomorrow to see what is going on. I'd appreciate any relevant feedback and ideas. :thanks:

After reading through this a couple times I'm not sure it's a clutch. With as long as you've been driving a manual I'm sure you know that the clutch isn't absolutely necessary once moving, especially on up shifts. Just get the revs matches it justs slides into gear. Ditto for downshifts though the rev match is tougher to do. No need to muscle it. The clutch just makes it easier for us mortals to rev match and saves syncros. If your clutch wasn't releasing fully reverse would be tough to get even more than first. My first thought would be to check the shift cables at the transmission. There's been a few break and maybe yours are on the way out. Do the same for the plastic ball ends. Recall reading that they've been seen to wear. It would also be worth checking the alignment on your shifter in case something loosened up or wore. It's a bit of speculation but if the shifter cables aren't working in sync for whatever reason they'll bind in the transmission. When the engines off nothing's moving to object. My experience with bad clutches are they either slip or won't disengage completely. When they won't disengage reverse and first are hard to get when stationery and downshifting into lower gears can be tricky when moving. Doesn't sound like what you're experiencing.

I appreciate the input. I did briefly check the transmission ball-end connections while the car was on ramps yesterday evening but I couldn't muscle the ends off, and both were still aligned in their cable slot things (w/out zip ties). Looked for leaks, bled clutch slave, all seems good on the outside. The clutch pedal feel is definitely off. Soft, and pickup seems closer to the floor and spongey, but with a shudder while releasing. Decided to tackle it whole hog. Step 1. Built these cribs off a model I saw online. Now that it is UP IN THE AIR I'll take a better look at the external stuff before I dig in. I'll post more as I go.

I would look at the slave cylinder first, then the master. It sounds like the clutch is not fully releasing. The fact that you can force it into gear sounds like using the synchros to overcome the residual torque of the not-fully-disengaged clutch. The shudder, I cannot comment on.

thanks ken. based on your comments and my subsequent research, I'm leaning towards the clutch slave cylinder. Clutch pedal behavior is what is pointing me in that direction. Maybe I can get home early from work tomorrow and take it out of the bore and check it out. Hope so, as it is $60 for a new one, not several hundred for a new clutch. Even a new master is only $160ish.

I would have leaned that direction too but when a clutch doesn't release all the way going into reverse usually makes ugly noises. Unless we've now got syncros on reverse too.

well, I removed the "one bolt" according to everything I've read to release the clutch slaver cylinder, and the cylinder will rotate a little, but.. There is this shift linkage thing right behind the slave cylinder (on top of the transmission) that is in the way of just pulling the cylinder toward the rear of the car and away from the motor. The fluid line to the cylinder was making it even more difficult to get the slave cylinder out, so I bit the bullet and took 30 minutes to finally loosen and remove the fluid line. What a PITA only being able to rotate that nut about 1/8 at a time, and can you say MESSY? I came in to cool off and clean up and see if I can figure out how I can get past that shift linkage thing. I haven't read anything about this or seen pics online. Last thing for today. I'm NOT looking forward to having to start the slave cylinder mounting bolt when I put a new one in. Man it is TIGHT up there.

well, I got the slave cylinder out. PITA to get it twisted and up and over the shift linkage thing I described that is behind it (toward the rear of the car). AND... drum roll please. The slave looked good to me. No fluid leaking past the seal on the rod side under the boot. Onto the master cylinder, but that is for tomorrow, as I got some brake fluid in my eye. Good times. I figured that I may want to replace both the slave and the master at the same time anyway. One consolation. I was due for my 2 year brake fluid flush anyway. :hilarious: So I'll do that once I've done the clutch hydraulics stuff. Related side note for Les. I read somewhere in my research on this that Reverse DOES have syncros.

Well, I removed the clutch master cylinder this morning. Not overly difficult, except for the contortions under the steering wheel and console on my back. Will be an interesting proposition getting the two bolts lined up and the clutch pin in place. Nothing obvious about the master cylinder being the problem either, I may be "just throwing parts at it", but new master and slave have been ordered. Will get some brake fluid while the parts are in transit, and hopefully later this week I'll put it all back together and bleed the system. bolt sizing info: Bolt that holds the slave cylinder to the transmission: 13mm Flare nut on the fluid line to the slave cylinder: 12mm two bolts that hold the master cylinder in place under the dash: 12mm pin w/ c-clip holds the clutch master rod to the back of the clutch pedal. (be careful not to lose the clip when you pop it off. w/only one hand available, I put a cloth over it when I pushed it off.

You can always drain the transmission oil if you suspect damage to the transmission. If you see lots of metal come out, then you know there's dying synchros in there. But sounds more like a broken clutch. I think there's been a few posts in the past where people posted similar symptoms and the clutch was the culprit.

Well, in the interest of full disclosure and hopefully to pass on some words of warning. I finally got around to replacing the clutch master and slave yesterday evening and this morning (too much work in the week), and I wanted to take my time. Anyway, other than the contortions to put the master in there and get the bolts home it master was fairly easy. The slave, on the other hand was a PITA. realizing that I had issues just pulling the old slave cylinder out of position, I removed the under tranny tray to provide more room. I manage to get the slave in there, but it was TOUGH. I bled the clutch (pedal against firewall), then all 4 wheels... then drum roll please. I manually pull/push the clutch a couple of times, knowing that it'll take a few strokes before it hardens. 6-8 cycles later it is still soft. I look at the fluid reservoir and it is down quite a bit. HUH??? I look under the back of the car and IT IS POURING fluid. D@MN, I must have not gotten the fluid hard line tight enough... quickly I slide under there and do my best to tighten the fluid line on the slave. Soaked in brake fluid. good times. I take the under tranny tray off again to see what I can see, and to clean it, 'cause I don't want brake fluid on my paint when the car gets rolling. turns out that fluid is coming out from the gap between the transmission and engine housings. F**King slave cylinder must have missed the clutch fork, and blew out in the bell housing. :wall: Shore enuf, I undo the slave and the front end is blown off, and much of it is still stuck in the hole. I about took a baseball bat to it. Anyway, I'm so pissed that I just said EFF it, and will get it towed to a shop on Monday. If they've got to separate the tranny from the engine, I'll probably get the clutch replaced (may need it anyway, if fluid managed to get to it??). Probably an RMS and LN IMS replacement. Moral of the story. Drop the tranny a couple of inches to give you room to get that slave aligned properly, or better yet, drop the tranny entirely if you've got to do the slave cylinder. Shorter in the long run. I will relay how bad they bend me over.

Sucks you're having this much trouble. I remember how bad the slave cylinder was to get back in when I replaced my clutch and flywheel. Sent from my iPhone using Tapatalk

Yeah. It wouldn't be so bad if the tranny was off the car. One would then just have to connect the hard fluid line, and be assured that the business end of the slave mates correctly w/ the clutch fork. From your experiences inside the tranny, do you think it is probable that brake fluid got past the pressure plate to the clutch?

Sorry you are having so much trouble.

its all good.. I appreciate the support from the group. I am taking the tranny off. thought better of it after cooling down. using waynes 101 Boxster projects book as a guide (and info from here). got a late start today, but have the exhaust off, and am now detaching the drive shafts. One tidbit on the exhaust flange nuts. Easiest way to get to all three on each side is to go thru the wheel well and use a 6-12" extension. Piece of cake going that route. Under the car there is no easy way to get to the inboard nut. Interesting on the LN IMS replacement. I did read something on their website yesterday that was special about the 06-08 model years. What about RMS? I'll take a peek when I get to it (assuming I take off the flywheel??) Anyway, making slow progress, but I'll probably end up putting in a new clutch anyway. (kinda like brake pads 2 months back. the fronts were 1/2 worn, and the rears maybe a 1/3rd). Anyway, I'm getting to learn my car better, so that is good. I think I'm done for the day. New puppy in the house and going to be playing w/ her. cheers all.:beer:

Good man doing the job yourself! I replaced everything except the RMS when I did my clutch job, clutch, flywheel, pressure plate, throwout bearing. Kind a wished I had done the RMS now. Sent from my iPhone using Tapatalk

Well, I dropped the transmission yesterday evening after work. Couple of pics related to my specific situation: You can see the brake fluid residue on the left half of the pressure plate and finger springs. So "while I'm in there", I'll be replacing the clutch, pressure plate, throwout bearing, etc w/ a kit. Actually, this was my main concern, and why I decided to drop the tranny anyway. Going to research the flywheel. I know that I can clean any moisture residue etc from it, but apparently there is some 15 degree test that can be performed to see if the dual mass flywheel is still good. I haven't researched what they cost new yet, so I might go there anyway? All input on this appreciated. LOOK at that cr@p in there. The slave cylinder push rod was up and left of the pocket. Anyway, I'll clean everything up, do some parts analysis and then put it back together. Couple of misc points regarding this episode: 1) The clutch fork pocket is actually pretty big. I don't know how I missed it. If I were to do JUST that next time, I'd remove enough stuff from the driver's side of the transmission so that I could be sure to get a straight push w/ the slave cylinder and be assured that the slave piston rod hit the pocket. 2) Using Wayne's 101 Projects book, I had to manufacture an open end wrench and torx bit combo w/ tape to hold the bit in there. The gap between bolt "A" and the transmission case was too small for a socket. 3) Again, using Wayne's book, bolt "D" was easily broken free from the passenger side of the vehicle. There is plenty of room there to push a ratchet upwards. 4) Attachment point "H" is a nut on the motor side of the junction between the motor and tranny. The tranny has a stud. Presumably to help w/ alignment when reinstalling the tranny??

Didn't get to look at it yesterday, 'cause my parents came thru town (much better use of my time anyway, so I don't take time w/ them for granted). I did take the pressure plate and clutch friction disc off. I'll be sure to check an OEM clutch disc thickness, but it looks pretty thin, and lots of black dust came out when I pulled the pressure plate. I feel I'm pretty easy on clutches. Maybe the clutch switch defeat is allowing it to be consumed faster? Ordered clutch kit and install tool, and a new SLAVE cylinder. Not to bash any sponsors on here, but I got them from RockAuto for a LOT less than elsewhere. Flywheel passed the 15 degree test, and looks and feels good. Just chillin' now until parts get here. What are the torque specs on the pressure plate bolts?? They were pretty light.

clutch kit arrived this afternoon. Son and I got it installed and the transmission back in the car. bought a tranny jack. Much easier than balancing on a regular jack, although it still took over an hour to get it lined up. Had to get a couple of bolts started (B and G, I think) and pull it together slowly. New slave cylinder, which I installed while the tranny was out of the car. It was fairly tough to do that w/ complete access to the insertion hole. The shift linkage that goes across the top of the tranny is a real PITA as for getting the slave cylinder lined up w/ the hole and mating surface on the clutch fork. Bled the clutch and now have a firm pedal. :banana: exhaust, sway bar, one axle to tighten, under tranny pan and rear bumper to install tomorrow??? Then off for a test drive and then it needs a serious wash. Probably even deserves a detail w/ the DA.

My fingers are crossed for you. I would assume you will take care of it by replacing everything.

Hoping for a fun and successful test drive that brings your transmission woes to an end. :drivingskid:

Well, I'm embarrassed to say that I've put it altogether and still can't get it right. I figure I'd post here to inform the community. New clutch and pressure plate (I only did this because after the first clutch slave missed the clutch fork I was concerned about brake fluid on the clutch friction disc). New clutch master cylinder New clutch slave cylinder New fluid. bled at all 4 wheels and at the clutch slave. was getting a lot of bubbles down to a few very small ones at the clutch slave when I stopped that effort. gears will shift fine w/ the motor not running. (although I have now exacerbated the driver's side shift linkage falling off... couple of well placed zip ties would take care of that). Will not go into gear w/ the motor running. Before the endeavor I would have to struggle to get it in when running. Will try to start and jump forward if the clutch is fully depressed and in gear (1st), so obviously the clutch isn't separating from the pressure plate and flywheel. Clutch position sensor works, because if I have it up the car won't try to start. feels like a clutch hydraulic issue, and maybe it is??? but I've had it. New rule for me: if it is a big project, I'm going to get a diagnosis from the pros first. Turning the wrenches wasn't that tough on even this project, but obviously I'm missing something. Hope it turns out to be obvious. I'm going to have it towed to Hendrick Porsche on Independence tomorrow AM and see what they have to say. Hope this helps someone. Kinda like a diary for me.

I hate that you're having this much trouble. I remember how long it took to bleed the clutch after my install. I didn't think the bubbles would ever stop.

brief status. Had car picked up by GMP (enclosed trailer, so that was cool). Tech says that the clutch pedal is "normal" now, so it is not in the hydraulics. Dropped the tranny and he said that all of the pressure plate bolts were "finger tight". Now, I know I took my time in a criss-cross pattern to tighten them, but w/ the 3 tight fitting alignment prongs off the flywheel, it is possible that I didn't actually get the pressure plate bolts tight down to the flywheel. I read somewhere here 11 foot pounds, but the tech told me 18#. Anyway, they're squeezing it in between other jobs and it should be ready Friday. I will update then. I haven't driven my car in ~6 weeks, and it needs a detail. They persuaded me to put in a new flywheel, although I'm pretty sure it could last through another clutch. I think I have a pic of it in this thread. Looks the same as the clutch being replaced in another thread right now. Their tranny drop/reinstall is/was ~$320 each way. I did ask them to take a pic of the RMS and IMS cover once the flywheel is off. (I didn't see any signs of oil on the motor, so, touch wood, I'm OK).

Good Luck. Don't worry about the missed 6 weeks, unless you really enjoy driving in the rain. LMK how satisfied you are with GMP. I may make use of their services.

Got my car back today. Feels GREAT, but I'm reserving a final "at a boy" until all of the nuts/bolts are assured to be tight. short version, and I'm not sure what the mechanics of the situation are, so maybe someone can elaborate. I don't think it was the clutch hydraulics (slave or master), although I replaced them. I think it was the clutch friction disc becoming narrower over time and the clutch wouldn't disengage fully when trying to shift. Then after I replaced the clutch myself, I apparently did not tighten the pressure plate bolts enough, and the clutch wouldn't disengage. Moral of the story, and the order I'd tackle this job again would be: 1) Bleed the clutch slave 2) Replace MASTER (it is actually easier to do than the slave) 3) replace the slave, but drop the tranny a little to allow better access 4) drop the tranny and check the tightness (or not) of the pressure plate bolts 5) Fully R&R on the clutch (and flywheel, if necessary). clutch pedal feels much heavier than my wife's CR-Z Cleaning the car now. FILTHY. c u on the road. Hope this thread helps someone. Labor on the tow and R&R was ~$900-1000. New Flywheel was ~$1050.

Great write up! I read each passing post like I was watching an episode of House--and you were methodically eliminating one condition from the next . I wanted to ask more about the "feel" of the clutch you experienced when your problems started...you mentioned that the engagement was "light and high." Was it that way for some time? Or did it only start feeling that way on the very day you experienced the problem? My clutch has disappointed me from day 1. To my untrained left foot, I'd guess I have about 1" to (maybe) 1-1/2" of engagement-zone. The clutch doesn't seem to bite until my foot is almost off the pedal. Pressure in the pedal feels fine (not spongey, not soft). I've had the brake fluid/slave bled 2x in the last 4-yrs with no improvement to the engagement of the clutch. The car only has 21k miles on it (2008 CS). Given your recent dissection of the system--any thoughts on what might cause such symptoms? (FWIW--I've had multiple other caymans (gen-II) and most recently a 2014 base Cayman as dealer-provided rentals. No issues with those clutches. They feel/behave like a clutch should!)

I just did the same think you described of missing the fork! Do you think you could have installed the slave from the top? Or maybe put a vacuum on the slave and pull the plunger in to install, I am at the same place you were, but only after replacing my clutch and pressure plate, I took the slave off as the trans was coming out and didnt think about installing on the ground before putting back in the car, but don't want to take the trans out again. Any suggestions?