Gene K

Lethal Performance (GT500 Left / 5.0 OEM on Right): Photo by BoostAddict


My Car (OEM): Photo by Intervention

As many of you know I have had issues with the clutch pedal sticking to the floor at anything over 6500 rpm. It would actually suck it to the floor when you got within an 1" and not return until 6100 rpm. Its caused by the design of the clutch rebound spring.

Lethal Performance (Week of 4/12 build) had the same problem but not until they turned up the factory rpm limit and it became more pronounced with an aftermarket clutch,. The Pedal Box Assembly on the top right is from the Lethal 2011 GT 5.0 and the large vertical rebound spring was binding and reversing force when it went past center. I believe is was designed this way on purpose to lighten clutch effort. The assembly on the top left is from a GT500 and was used to cure their problem.

Week of 4/19 was Volcano Shutdown

On my 2011 GT 5.0 (Week of 4/26 Build) I didnt have the same pedal box assembly. I had what appeared to be a hybrid of the two. I had both clutch rebound springs. The shaft mounted one (like the GT500) and the separate vertical coil spring like Lethal. On mine I simply slid the lower coil spring mount off the pin and removed the large coil spring. Clutch effort rose from around 20 lb to 30-35 lb. No more stuck pedal and lightening fast pedal returns.

Edited to add photo.

montreal ponies

Gene, glad to hear things got fixed. Is this a Ford "fix" ? And does that mean that all cars with a build date of 4/26 and prior that are experiencing the same issues with their clutch will get the same fix as yours. Thx for sharing

Gene K

First some of the clutch parts were hard to get. (Engineering wanted my entire assembly from pedal to flywheel for testing).
Second Fedex lost some of the parts,
Third Engineering sent a hold as they wanted to send a different pedal pedal box assembly than the GT500 (Which likely raises pedal effort) they originally sent.
Fourth the Service Advisor at the Dealer Left.
Fifth they discovered they dont have his Computer Password so all the communication from engineering about my issue is in never-never land.
Sixthth a little Blue Bird in Livonia gave me permission to try my own fix.
Seventh Im in hiding as I really dont want something that isnt broken (anymore) fixed. Im afraid they may put an assembly that has some reverse force just less in my car, the issue may resurface when I turn up the rpm limit. If its made like Lethals it wont be as easy a fix. I will have to buy a GT500 Assembly.
Eighth I really dont wont my car tore apart if its not necessary .

So its an unofficial fix thats unofficially unapproved.

Intervention

Glad to hear your problems may have been fixed...

I am also having some clutch issues with my 5.0, but just a bit different.

We all know how soft/light the clutch pedal is stock on these cars, its a huge difference when compared to my old 07 with an aftermarket clutch. Anyways, about 4-5 days ago, something has changed in my pedal feel.

The first 45-50% of my pedal travel is still, very light. But the remaining portion, the weight increases dramatically. Also, the pedal engagement is now less than 1" off the ground, not towards the top as it used to be.

No idea what could have caused this, I have an appointment with the dealer tomorrow. Looks like my 100 powershifts at 7200rpm might not have been a great idea...

montreal ponies

oh right..... then i'm just hoping i won't experience the same issue with mine.

Adam

I guess so.

montreal ponies

Just don't mention it.

825LTRGT

I've driven two '11 GT's with 6/11 build dates. Both of the clutches engaged about 1" off of the floor.

Hmmm!!???

montreal ponies

Keep us posted and start a new thread on it.

Driver72

I read a day or two ago where somebody else did this same thing and also mentioned the pedal effort increase as you did as well.

I'm hoping there is a factory fix however. Maybe by the time my car is built and delivered in early to mid September.

foolio2k4

do u guys have a thumping noise when u shift from 1-2 and 2-3? Or even a rattle as if its grinding when going from 2-3?

Gene K

I didnt. Felt exactly like an over-centering Diaphragm Clutch. No other symptoms.

Gene K

Deleted

Gene K

Bump so everyone can see the new photo.

m4reapr

i just visually confirmed that my car has the hybrid (both springs) pedal setup

car was built on 5/04 according to online sticker, 5/10 according to doorjamb sticker

the clutch pedal feels fine either depressing or returning, no binding
it does feel like the most pressure is in the middle of travel, light up top, heavy in the middle and light at the bottom (floor)
no sticking to the floor, i ran close to redline on a 1-2 shift bringing it home and it worked fine

clutch takeup also feels close to the floor though i haven't driven enough (79 miles) to say if it is an inch or 2 or whatever

Driver72

Maybe I'm a tard, but help me understand how the clutch pedal sticking has anything to do with engine RPMs?

Whether you are spinning the engine at 2000 rpms or 7000 rpms, how does that affect the clutch PEDAL and the spring sticking and holding the pedal to the floor?

Is it nothing to do with engine speed, but more to do with how quickly you are power shifting the car and it's just that aspect that's causing the spring or whatever to catch up and stick to the floor?

Gene K

First a definition of Overcentering:
Overcentering is when the diaphragm spring’s fingers get pushed past the normal centerline of the diaphragm spring. When this occurs, centrifugal force acting on the weights and diaphragm spring keeps the fingers of the spring bent down causing the clutch to stay disengaged during high RPM shifts. Overcentering can occur with any diaphragm clutch but centrifugal assisted clutches are especially sensitive to this. If you can feel the pedal get lighter with increasing revs, that is the clutch wanting to overcenter. All diaphragm-type clutches are prone to overcenter to some degree.

The clutch isnt going far enough to actually overcenter but is getting lighter at higher rpm. With the factory clutch pedal rebound springs both in place I can put the car in gear and push the peddle down to 1" off the floor and rev the engine. When the rpm hits 6500+ the pedal will leave my foot and go to the floor. Pop it in neutral and release throttle and the pedal will pop back up at 6100 rpm. If you pull up on the pedal it takes 5-10 lb of force to overcome the spring pressure and pop it off the floor. I suspect tolerances on my car allow the clutch to come closer to over-centering which is why the improved 4/26+ dual spring assembly that came on my car didnt fix the issue on my car.

Lethal Performance has a Video on You Tube showing their OEM Pedal Assembly in a vice and what happens when the pedal is pushed. When the pedal goes so far the coil spring binds in the middle and starts compressing part of the spring which causes the pedal assembly to snap fully depressed. At low rpm the clutch pressure is enough to resist this no matter what. At high rpm near fully disengaged it isnt.

Driver72

Thanks Gene.
Well I have a VIN now for my car but it hasn't begun to build yet.
I know it's probably wishful hoping but maybe Ford has "fixed" this issue by the time my car is built.
If not, guess I'll have to do what others are doing and fix it aftermarket.
I really don't want a heavy clutch pedal though. In LA traffic a heavy clutch pedal sucks.
My buddy had an Audi S4 and I was surprised at how butter smooth and easy that clutch was on an AWD V8 performance car. I liked the idea that the 2011 GT's clutch pedal feel was like that.

BLKCLOUD

Eh...I bet it will feel like the good old days of a simple clutch cable setup with the fix Gene's describing. And you're left leg will get used to it in not time flat...kind of like my left hand pulling on my Harley clutch; its tough when you first start doing it, but those little muscles build up in no time flat and it becomes no big deal.

corvettedreamin

This sounds like a design flaw to me. . . and ultimately a safety hazard given the operational description. And if so, will result in a recall.

I'm going to go out on a limb and say the clutch pedal assy is the same in the V6. My car was built 5/4. No issues so far. . .