Blacksmoke

It sounds like you DO have the TSB problem.
You are exhibiting multiple symptoms of the TSB.
The hissing when the car is in gear and you are not using the clutch, and the creeping forward.
You need to put your parking break on.. have the car shut OFF, and see if the car will go into gear WITHOUT pressing the clutch.
If the car DOES do this in any gear... you also have a syncro problem with your tranny that will have to be fixed.
If not... you need the whole clutch assembly INCLUDING the flywheel replaced.
Remember the flywheel is the actual source of the problem. With the TSB problem it warps.
The clutch is one of the things it ruins.

I do NOT recommend SPEC.
There are way too many NIGHTMARE stories on SPEC's in these cars.
The 3+ has had more success than most SPEC models but there's NO WAY I would buy from SPEC.

I myself had a nightmare with them. I was warned before hand but by only one or two people and I
ignored the warning. I ended up paying BIG TIME for not listening.
Plus they treat customers like CRAP. They treated me UNBELIEVABLY rude.
With each person but one that I called and I called them over five times.

FINALLY I got ONE honest person over there that admitted to alot of complaints with the clutch I bought from them.
Guess what? THEY STILL did not stand by their product for me.
I had to eat the cost of both a new clutch AND taking the tranny down again.
I took that damn thing out and threw it in the trash. I would not even attempt to sell it privately to another person even though it was a brand new clutch.

Look on these forums as well as others. You will find that SPEC has ALOT more horror stories than other brands out there.
Ask the very knowledgeable people on these forums that have been here a long time and have been into Mustangs and worked on them. You will find I am telling the truth.
I and others will warn you against SPEC.

In my opinion if you get a good SPEC clutch you are LUCKY.
I WOULD STAY AWAY FROM SPEC.

Get either the new updated clutch assembly for the GT500's, a Mcleod, or an EXEDY (I believe they make one for the GT500, I replaced my SPEC with an EXEDY for my 06GT and it was WONDERFUL)
Any of those clutches are a great choice.
And in my opinion SPEC clutches for these cars are GARBAGE.

Lifter583

Smoke...I know your problems with Spec and I respect your opinion...I have a friend who drags with Spec clutches exclusively and three GT500's in this area that have Stage 3+ in them without a bit of problem...I have a stage 2 in my GT which performs great...so for me I have no problem going with the Stage 3+ in my GT500...

BIGPHIL

@Blacksmoke
There are more horror stories about Spec clutches because I would be willing to bet more people use them (and often the wrong one because *** clowns give them bad information to begin with...not pointing fingers at anyone). For the s197 platform, the Spec 3+ is the best choice for v6/gt/gt500 (stock or modded) out of the Spec lineup. They hold big power and have the same pedal feel as stock which is crucial for a daily driven car. I cant say I have any experience with their customer support so I wont, but I do have a lot of experience with the McLeod RST. We can go back and forth on this subject all day and neither of our opinions will change, so lets leave it at that.

@OP
You have enough information to decide what to do if you end up getting an aftermarket clutch...good luck with whatever you decide to do!

Blacksmoke

In my case it was the SPEC people that were the assclowns that told me the wrong clutch to use if that is the case lol.

Actually they told me a 2+ was great for the street and after the horrible problems I had and the horrible noises I got with no fix, and five or more phone calls later... I finally came upon a SPEC employee that told me not only was the 2+ not good for the street and everyday driving, but that the clutch had complaints and problems all the way around.

My biggest problem with them was the fact that they did not stand behind their product and I had to eat the cost of another clutch and dropping the tranny again... AND how I was treated on the phone.

I understand all clutches have some that end up lemons.
But when some companies tell me they stopped selling SPEC because of the problems AND SPEC admits to the widespread problem themselves on the phone, that tells you it is not just because more people are using them.

I say again the reason I won't use them again really isnt because they had a bad model. It is because of the treatment they give their customers and how they failed to stand behind their product.

I for one want to make sure I buy from a company that respects and values their customers as well as makes SURE the customer's problem gets fixed when the problem is not of their own fault.

I have heard the SPEC 3's are a much better clutch and do not have as NEAR the problems as the 2's.
I have no problem believing people are running the 3's with no problems. I have heard that A LOT.

BIGPHIL

For the benefit of other readers that come upon this information in the future...we are talking about the Spec stage 3+ here....NOT THE 3. 3+ good, 3 bad

@Blacksmoke
I do have experience with the 2+ not being street friendly and loud (my dad had one), so I will agree with you on that for sure. Hopefully their customer service has changed/changes, because that is just straight horse crap to have poor customer service...not to mention THEM telling you to get a 2+...totally stupid. I bought my stuff from LethalPerformance and they have awesome customer support and will usually deal with the manufacturer directly if there is an issue with a product you purchased through them. Sometime you can find a better price, but when it comes to big ticket items like this...its worth a little extra money for good support.

Blacksmoke

I heard Lethal was a great place to buy from many people.

Blacksmoke

LOL that 2+ had NUMEROUS issues.
Not to mention people next to me on the road literally though I was honking at them from red lights.
Like I said I had to ditch it brand new and eat the cost of another clutch AND the cost of dropping the tranny again.
And I have never had a company NOT stand behind their product the way SPEC did not stand behind theirs for me.

But I mean if only one model (The 3+) has gotten a good rep from most people, which is the case... and the customer service is bad... which is the case...isn't that enough to tell you to stay away from them?

I just can't have confidence in a company like that.

BIGPHIL

Good thing I do my own work. Pulled my tranny 4 times to get a clutch to work...after that many times, I had to dump the RST.

Only two big names that had enough reviews were McLeod and Spec...only one option left for me at the time. I have heard some decent things about Centerforce, but their website and the information (or lack of it) on their products is the only thing that kept me from them. I'm sure there are other decent brands out there, but the 3+ is ****, even if the company is a pile of crap and treats the customers like garbage...just wanted something that worked!

Blacksmoke

Dunno if the EXEDY was out when you bought yours but they make an EXCELLENT clutch for the Mustang GT. Ford Racing uses them as well now too.
Lots of good reviews on EXEDY as well.
Again not sure if the info was out there when you got yours.

Also not sure if they make one for the GT500 though.

BIGPHIL

I'm pretty sure they were out, but there was not a whole lot of info at the time I purchased mine about the Exedy. I was so fed up with the situation that I had to get something that I had never heard anything but good comments about, and it was the Spec 3+. Centerforce was also out at the time, but many more bad remarks than there were good, but I have heard the opposite now...that the Centerforce clutches are pretty sweet too. A few others out there too, but I'm happy with my choice and it has paid off well for me. When its time to change it out, I'll review my options again.