Clutch & Flywheel Replacement

[Xcentric]

New clutch assembly, throwout bearing/slave, flywheel and pilot bearing installed this week. New half shaft bolt kit too, because several ounces of transaxle oil got past the flange seal. No external leaking, but the flanges were full of oil.

I had the clutch replaced at 31k miles, because the engagement point had reached the top of pedal travel. It wasn't slipping, but I figured that was next.

Surprisingly, the clutch disks were not worn much. 7.5 mm vs. 8.0 mm new. However, the engagement point is now back to the middle of pedal travel as it was when new. Beats me.

The flywheel and pressure plate looked pretty bad. I've heard about "hot spots," but didn't know what that meant.

Here's the flywheel:




Pressure plate:





Close up of flywheel:





As I hope you can see in the last photo, the hot spots are worn below the surface. You can feel the indentations with a finger. I have no idea what the physics is behind this phenomenon. Weird.

The new clutch (OEM) feels great.

EDIT: A few googles and I learned that the hot spot areas are a different hardness from overheating than the rest of the flywheel, which causes uneven wear. Still don't know why some spots get hot.

 

[CanadaGT]

Mine looked like that after 76,157 miles and approx. 15 sets of rear tires. Replaced it with oem stuff as it is Ford Tough in my world. I religiously changed clutch fluid every oil change.

 

[partssmann]

Was your GT in any stop and go parades? GTs and parades are a bad mix and can be the death of our clutches.

 

[Kayvan]

CanadaGT,

How many oil changes ?

Annual, @ 3K mi. or other interval ?

Thx

 

[CanadaGT]

I drive a lot on the highway but probably 20 oil changes. I am a Licensed tech so I do all my maintenance and repairs. The amount of fun I have had in this car is truly amazing. also at least 20 changes of clutch fluid is why I think my clutch held so long. I work on a few of the local guys cars regularly.

 

[PeteK]

Why would changing clutch fluid frequently have anything to do with how long a clutch (pressure plate and discs) lasts? Doesn't make mechanical sense to me.

 

[ultrasportracing]

You are correct. the two are not related

 

[texas mongrel]

Mine looked similar at 40k miles, disc was not too bad but flywheel was burnt. Only downside after fitting new parts was that the new throwout bearing (old one was fine, but changed just in case) now howls like a cat in heat!

 

[CanadaGT]

Check the color of your clutch fluid, my guess it is black, which indicates break down of the fluid. I use penzoil Dot 4 synthetic and it keeps the clutch pedal light in feel and the fluid is not contaminated by heat and releases properly. Dirty clutch fluid makes for a lazy clutch. FYI I drive the shit outa my car after it is warmed up. Other GT guys will attest to this issue. Just my opinion

 

[Kayvan]

Why would changing clutch fluid frequently have anything to do with how long a clutch (pressure plate and discs) lasts? Doesn't make mechanical sense to me.

If it had no impact then clutch fluid would be for lifetime of car.

When fluid degrades (moisture, heat, contaminants) it effects engagement/release , slippage, grinding,
Spongy pedal.

Non optimal actuation has to result in wear OR Driver input error to compensate (slipping/lugging)

 

[PeteK]

Kayvan, you're missing the context. If the clutch fluid is so bad that it's boiling or turned to goo, yeah that will make a difference in clutch feel. If the fluid is merely okay or better, it won't make any difference in the operation of the clutch.

The main reason clutch fluid is not "for the lifetime of the car" is to prevent internal corrosion of components due to hygroscopicity. You change the clutch (and brake) fluid to get rid of moisture contamination that builds up over time. But changing the fluid 20 times in a few years makes zero difference in clutch operation.

It also makes zero difference in how long a clutch pressure plate and disc lasts. Longevity of those parts depends only on how the clutch is used, or abused.

 

[DakotaGT]

Check the color of your clutch fluid, my guess it is black, which indicates brake down of the fluid. I use penzoil Dot 4 synthetic and it keeps the clutch pedal light in feel and the fluid is not contaminated by heat and releases properly. Dirty clutch fluid makes for a lazy clutch. FYI I drive the shit outa my car after it is warmed up. Other GT guys will attest to this issue. Just my opinion

I just changed my hydraulic clutch fluid a couple of days ago, and asked Rich (GTGuy) for his current recommendation, and he told me to use Motorcraft 5.1 brake fluid. I’m sure there are several good choices out there, but just an FYI.

 

[Propdave]

I can attest to the change in pedal feel when the clutch fluid in my car was changed. My clutch fluid was also very dark compared to new. Given how inexpensive the fluid is, plus easy and fast to change, I felt it was a no brainer.

 

[PeteK]

If the fluid was dark, then it was well past time to change it. Any idea when it was last changed? How did the feel of the pedal change?

 

[TO AWSUM]

I just changed my hydraulic clutch fluid a couple of days ago, and asked Rich (GTGuy) for his current recommendation, and he told me to use Motorcraft 5.1 brake fluid. I’m sure there are several good choices out there, but just an FYI.

I also use Motorcraft 5.1 now, not to be confused with 5 which is a big NO-NO.

 

[BlueGT]

Mine looked similar at 40k miles, disc was not too bad but flywheel was burnt. Only downside after fitting new parts was that the new throwout bearing (old one was fine, but changed just in case) now howls like a cat in heat!

I know this is an old thread, but can you tell me who changed out your clutch/flywheel....and did replace with OEM or aftermarket kit?
Many Thanks,

Pat

 

[nota4re]

Hi Pat,

We've done a couple dozen or more clutch changes on the GTs. We've used the OEM and SPEC clutches - and maybe one Stillen in the distant past. Of all of them, we still really like the OEM clutch unless you have a highly boosted Whipple or turbos - then we might recommend the SPEC.

 

[nautoncall]

How do I change the clutch fluid?

 

[nota4re]

The small size of the GT clutch reservoir pretty much insures that you will really need to change it at a minimum of once every 5-years. If you've never flushed it before, it CERTAINLY will need it after 14 years!! Most likely the fluid will be almost black and somewhat "snotty". (I know, gross, eh?) Our recommendation:

1. Place a blanket over the fender and have a clean, really wet towel nearby. If you ever manage to get a drop of brake fluid on any part of the GT, use the very wet rag to immediately dilute and wipe it up.
2. Use a syringe and suck ALL of the fluid out of the reservoir. Discard it responsibly.
3. Use a cloth or paper towel and clean the heck out of the reservoir so that it looks nice and new.
4. Fill the reservoir with clean, fresh fluid.
Note: The next steps we do with 3-people. Ryan and I will draft Cindy or Lauren into service to be the "fill master".
5. Locate the clutch bleed nipple back near the bellhousing (Passenger side), clamshell open (obviously). Attach a clear silicone tube to the nipple and use the box-end of a 10mm wrench to crack it open (not yet). Person inside the car with no shoes (important), pumps the clutch pedal and yells "down" to aforementioned "bleed master". Bleed master opens bleed nipple and closes it after a squirt of fluid comes out... at which point he yells "closed". Inside car person lifts pedal back up using toes and pumps it a couple of times and ends in down position shouting, "down". All the while the drafted "fill master" is insuring that the reservoir remains close to full. After about a dozen iterations, the fluid coming out will be the clear good stuff.

That's the routine at Cool Tech.

 

[nautoncall]

Thanks as always Kendall!!