John SCB

I just had a Centerforce DYAD clutch (with a new slave cylinder and pilot bearing) installed two days ago. The clutch grab point is rather violent and even difficult to predict. Sometimes it grabs hard with the pedal close to the floor. Driving at freeway speeds gives the pedal a much lighter feel, although the grab point is much higher up than it is when driving around town

The installation tech at the speed shop told me to expect a "dead pedal" feel to the clutch when it's cold for the first day or so. He said it has something to do with building up hydraulic pressure. Pumping up the pedal a few times before driving brings the correct pedal feel back. I sure hope this is indeed a temporary issue. I can't help but wonder if the clutch bleed was done correctly?

I've put about 100 miles on the car since the install. Has anyone else had this same issue going on?
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pebkac

It has been a long tim esinc eI first read this. But I think it goes like this. Jack up the drivers side of the car. Get in and pump the clutch pedal. this should bleed it also. This may only be on the factory slave however....

John SCB

Thanks for that. When I showed up to get the car on Wednesday, they were just lowering the front drivers side down with a floor jack. Interesting to note that your post supports that method of bleeding.

I took it back to the speed shop yesterday afternoon. I expressed my concerns. The tech was cool about listening but said that "all mustangs have the same bleeding issue for the first day or two after clutch installation". I told him it hasn't really improved since I picked it. I'll put some more miles on it over the weekend. If there's no improvement by Monday, I'll bring it in and have them do it again. I got the impression that the guy may not have bled it per the factory procedure; only because he appeared to be unsure if it had a bleed valve underneath the car. I've heard that the '05 had that bleeder screw but subsequent years did not

I then asked about the vacuum bleed at the MC but he said he never has to do that and doesn't really want to. He explained that the air eventually clears in the line even without bleeding. The impression I get is that he just doesn't want to spend the time doing it if he doesn't have to.

One thing is for sure: this is a heavy duty high performance clutch and not as smooth and quiet as the OEM. Hopefully that will change after the break-in period (recommended 300-500 miles of city driving). I can definitely feel a more positive transfer of power, especially at higher rpm's when the supercharger really kicks in.

pebkac

Well gLad I got pretty close to right from memory... I did mine a few times and my clutch has not been replaced still factory. It felt better after each time....

Lime GT

The clutch slave will self bleed by pumping the pedal. I removed the pedal assy in my 05 to repair a squeaky clutch master cylinder and brake pedal groan in the booster and it took about 40 pedal pumps to get the air out of the system. A week later I removed the trans to change my clutch slave cylinder as it was noisy and stiff as well. It took a lot of pedal pushes, to get the pedal feel back, like 300 I'm guessing, since the cap I used to hold fluid in the line fell off and all fluid was lost. I did it with the car level and still on stands. I don't know what stage of clutch your using as I haven't researched them but with the miles you've put on I'm guessing it's just the high performance trade-off of not using a oem clutch you're feeling.

John SCB

So you don't recall seeing a bleed valve at the slave under the car? I was told the '05 had it but later models did not. I'm beginning to doubt this as I can't find any supporting evidence other than what the tech "thought" it had.

I've put another 100 miles on the car this weekend. The pedal is somewhat better but it's still not right. I no longer have to pump it up from a cold start. There is still an occasional squishy feel and the grab point is very high on the pedal (about one inch from the full up pedal position). It would seem a vacuum bleed is the only sure fire way to get all the air out. It's annoying to have to take it back in for something that should have been done correctly the first time after the install.

Lime GT

Yes there is a bleed on my 05 but it's so tight to access. Maybe if I'd tried using the bleed screw while the trans rear end was hanging down held by my jack I may have had access. I never thought of it until the trans was totally reinstalled. You can try to bleed yourself if you have a mityvac http://www.mityvac.com/ . You can use a cork or reservoir cap with a hole through to attach the hose to and draw a vacuum and let it sit to draw air. I used mine a little when I couldn't get the pedal to build after about 30 tries. Whether it helped I don't know, I just keep pumping the pedal fast then slow then very slow until I started to get resistance. Ford actually uses the cork bleed system for power steering noises. It was in my old 92 Lincoln LSC manual.

John SCB

I suspect this is the same situation my tech may have been in when everything was put back together again. Thanks for the input. I'll repost the results when this thing is resolved.

LivinTheStangLife

this is why I hate hydraulic setups

they can be better than cable in terms of less pedal effort and take less space and stuff but I like having the cable and physically feeling it move the clutch and I like the tension that cable has compared to hydraulic. hate pushing on the clutch and it nearly feels like pushing down a piece of paper. also then you have to worry about air in the system and stuff. had a ranger with all new slave cylinder and clutch master cylinder and that thing still wouldn't ever work right, like it would always find a way to get air in it....

Cavero

I just had my clutch replaced 3 weeks ago (McCleod Street Pro), along with a new slave cylinder. The speed shop said there wasn't any bleeder, so you just have to let the system bleed itself over the first couple days. Picked the car up on Tuesday, and by Friday it was good to go. Just had to pump the pedal if it had sat for more than a couple hours. For the first day or two, I pumped it every couple stop lights too

Imatk

The shop should/could have bled it, but I don't think that's your issue.

I had a centerforce clutch in my car for three days before I pulled it out.

The clutch pedal is very "on/off" and heavier than stock.

I've heard good things about McLeod, but I don't have any experience with them.

Cavero

They're very smooth, I like mine. I've been told by my shop that the RST is a problem in heavy traffic because the tolerances are so tight. Once it really heats up, thermal expansion becomes a factor and it starts dragging. Otherwise, they've had great results from all of their customers with McLeod.

Mine buzzes under acceleration between 1500 and 2K RPM, but I've been told that's a common side effect of aftermarket clutches in general. Just seems to hit a natural harmonic in the drivetrain

John SCB

Update: It's been two weeks and 400 miles since the shop vacuum bled the system at the master cylinder. I would have felt better if it was bled at the screw under the car. The pedal is more predictable but it still grabs very high up on the range of travel. It feels like a thin clutch on its last leg. There is no detectable slippage, although there's only about 1 inch of meat on the pedal before it's entirely engaged.

The OEM clutch had a pedal grab at about mid-range and was entirely predictable. I also have have that annoying buzz mentioned by Cavero above.

The bottom line is that I don't like this clutch at all. I still don't know if it's the clutch, the slave or the install.

Imatk

If it's a centerforce... it's the clutch.

John SCB

Final update:
I finally got fed up with the slipping, dragging and chattering of this clutch. Despite the install shop telling me (3 times) there was nothing wrong, I told him to take it apart and check things out. He calls me to say there's a "hot spot" on the FW and PP, but not too bad. My mechanic buddy goes down to the shop and took photos showing two hot spots at 180 degrees apart on both FW and PP! Clearly one or both components were warped. The most annoying part of this experience was that each time I took it back they said everything was normal. The guy at Centerforce said based on the description of the damage, the problem was caused by bad hydraulics (which I suspected from the start) or excessive heat...something I doubt because I broke the system in per instructions, no burnouts, high revs, etc.


I had them install a brand new Ford OEM clutch kit. So, after nearly $2k, my clutch is back to what it was before. Like brand new.


Moral of this story: Stick with OEM parts and trusted technicians.

ford4v429

two hotspots 180 out is scary, sounds like something wasnt put together right somewhere in there...hydraulic issue would just make it engage close to the floor (just went thru this- put a new disc only in mine last week, the bleeder is a joke, jacking the drivers side helped, vacuum bleed helped, finally vacuum bled with car sitting drivers side high, perfect first try...)

my 06 has the bleeder screw, but IMHO its useless- the line from the slave comes out and bends down to the bellhousing hole...MUST raise the drivers side a bunch to get air from top of slave to master... to get all the air out of the slave, the high point needs to be at the rear slightly- so driver side way high, nose a little down, bubbles can migrate back to the plastic fitting- however, if your fitting has the bleeder, the bleeder itself is uphill now- let alone inaccessible... while tranny crossmember is still hanging, you can bleed the bleeder, but its so far down its completely useless.
park sideways on a steep hill, very slightly nose down, pump up your mightyvac with a stopper in the master, let it sit a few minutes, done.
I'm pretty sure there will still be a tiny bubble in the tee fitting just under the bleeder, but it musta always been there...my 06 clutch feels just like the 09 clutch again- and a ford disc from newtakeoff was only 50 bucks

I was surprised, my pressure plate and flywheel still had the machining marks showing, just a little discolored, but the disc was .050 thinner than the new one, all the grooves were gone- it had been chattering/getting really grabby... many, many 1/4 mile shifts on the rev limiter, even a stupid try of launching in 2nd gear had taken its toll on the disc, but the steel parts were in incredible condition. just scuffed the steel surfaces with 400 to get any glaze off, added a little grease to the throwout with a needle, smooth as silk again (after bleeding). man before bleeding, it was hard to drive...very glad someone in here suggested jacking the drivers side- got me to look at pics to see why, noticed the 'trap' Ford inadvertently designed into it... was the first time I ever used the little vacuum pump on a clutch master, man was that easy

hopefully at just 60,000 miles, I wont regret cheaping out on the pressureplate/slave, but time will... I had a squeaky pedal also, oiled it up and its quiet now- but what a junky looking plastic assembly THAT is...I would expect the plastic pedal/master assembly might wear as much as the clutch

John SCB

Thanks for the feedback Tim. I'm nearly 2 months into this new OEM clutch. It grabs where it should. It feels like it did when new. The only concern I have now is a kind of a "lumpy" feel to the drive train; barely noticeable to anyone that has not owned this car since new. It's particularly evident at idle in neutral with the clutch pedal up. I'm now wondering if the shop balanced the flywheel correctly. I would not have minded the extra cost for a new one if that's what it needed. My mechanic buddy wants to take it apart and check things out. Why is it so difficult to find a shop that does everything right the first time?

ford4v429

'lumpy' feel? like vibration at idle/no clutch pressure?

I wouldnt think pushing the clutch would affect this, but:

might sound silly, but the day after I put mine in, noticed one of the muffler tips was sticking out a little further than before- put it back on the lift, loosened front and back clamps, one of the rears popped in near 1/2"! after getting the rear back where it was, the one front slid back a little- it had a fair amount of pressure on it too- I musta tugged pretty hard when sliding the clamps back onto the midpipes... I didnt noticehow bad it was vibrating until after realigning the pipes, it felt a LOT smoother at idle...glad I noticed it, as it musta been shoving forward on the motormounts enough to possibly hurt a manifold down the road... after just loosening the 4 band clamps, shaking them a little, sliding the rears so the tips were flush, everything hanging bind free it idles smooth as silk... really easy to check, might sound stupid, but...

John SCB

Dauumm...that sounds totally plausible! I did have some exhaust alignment issues going after all of this work was done. I noticed one of the tips is tweaked up higher (and maybe further out) than the other. I'll get it up in the air and check it out. Will let you know how it goes. Thanks for the feedback!

bob

+1 I've got over 50k on my RXT and its still going strong