Is it any way possible for a clutch issue similar to what is going on with EVO's (possible decelleration noise and/or premature wear)

Could these symptons point to a problem which could cause gear shifting to grind also?

My gearbox is shifting pretty smoothly at 7200 miles, but going into first while rolling does cause a grind every now and then and when shifting into 3rd, I can feel a slight mild, like almost wants to grind feel.

 

wow, didnt think it could happen to me.... buit BAM!, 4500 miles and now the slippage began.... launched my car less than 8 times in its 4.5 month life..... slippage is evident with the revs (catching up)...... sucks

2COOL- how is the Exedy Single disc, is it hard to drive in the street? would you be better of with the twin disc?

-Shahul

 

This thread has gotten a bit off topic.

As an evo owner the seemingly tender clutch disk is the first thing I noticed. The three persons besides myself who drove my car had trouble with their shifts. Jerky shifts and too much slipage from a standstill causing the clutch to give off an acrid smell. I am talking about normal driving not a race start here. I no longer let anyone else drive it. I have professional driving experience. have owned and or driven a few HOT cars over the years so I have made a few shifts with a number of different clutches. This said, it is my considered and strong view that the Evo 8 has a problem here.

 

Your welcome to put an ACT in my evo course you would have to fly out to Atlanta

But I have already talked with my regional parts/service manager about the clutch being responsible for some of the decel noise and he was willing to let me put in an aftermarket disk at there expense.......

 

How so?

It appears that there could be a NUMBER of unique problems stemming from the EVO stock clutch, and the grind into second could be ONE of them....

I don't have any clutch slippage problems, but it would occur to me that the pressure plate is not stopping the disc with an effective enough "bite" to allow for the next gear to be selected and shifted into (second gear) and thus causes a grind or "cough"...

Does this make sense ACT man??

 

 

It would if the pressure plate has lost a sigificant amount of it's original 2200lb of clamping force. I am just waiting to see some blown up parts before rendering judgement.

 

Is this a potential warranty item or??

6000 miles on my car...

Grind in second, rough going into third sometimes..

Geez, the possibiltyies of needing a clutch at 6000 miles on a performance car is RIDICULOUS.. I don't have slippage or anything, ansd in normal non spirited driving, all is good..

NO launches to date BTW..

I drive my car effeciently, but haven't been abusive to it, that's for sho..

 

Reason he agrees with me saying it got off topic is because the original post I said to keep it on just the clutch and the miles at which you replaced it.
Honestly the conversation is very good so even if it has strayed some, who cares.

 

To respond to your question. When you depress the clutch you disengage the input shaft of the transmission from the drive of the flywheel. This allows the input side to slow to match the output side which in turn allows the next gear to be selected in a no load condition (no torque applied to input shaft) and lets the synchros match the gear speeds and lock into place thus appying the next gear.
This may not be a perfect explanation but it is close.

My point about the pressure plate contributing to your problem is the pressure plate lacking or losing it's mechanical advantage in relation to the piston travel of the master cylinder. Thus it takes more pedal travel to get the clutch fully disengaged, requiring the pedal to be fully depressed against the stop just to get the presure plate fully released. How this takes place is where I was originally going with the weak or flexing fingers that actuate this movement.
As an example, a bent clutch fork would not have enough travel to properly release the pressure plate. On old cars, misaligned Z-bars would cause the same symptom.
I don't know if this is contributing to your problem but it is within the realm of possibility. Like ACT said, once he actually sees the failed parts and can test them, he can't pass judgement on what the problem appears to be.
I hope this at least makes sense.

 

Ya Know Timz...

The service manager told me (as we were chatting while he took me to pickup my other car after dropping off the evo for the tranny replacement) He was specifically told by mitsubishi that "you have to push the clutch all the way to the floor before shiffting in the evo, they said if you don't you will grind the shifts".

Just some food for thought in relation to the spring tension topic. Is it possible that mitsu intentionally put a pressure plate with low clamping force (Spring tension) on the US evo to try and protect the drive line from the abuse that AWD and sticky tires can place on the drivetrain..........

Or maybee the manufacturer had a bad run of materials or a flawed heat treating process or something...

Guess we will find out after ACT takes a look, at least in the case of the owner whos parts they look over.

 

wow really mad viii? that is tite i have a appointment at my dealership cuz part of my passenger side dash/thing that comes off of the side mirror is gettin ***t up and scratchin my paint on the inside.... i will ask them about this...

 

I will certainly be able to tell if the pressure plate is up to par and if it is making the clamp load in the correct working range, etc to theoretically hold or not hold the power. I don't think I will be able to tell anything about the gear grind problem without vehicle testing.

 

ACT man..
We await your findings!!
Looks like your clutches will be purchased to replace the sub-par Mitsus clutch if the theories prove true..

 

I am still not convinced. Here is a photo of the Subaru US STI clutch (left) vs. Mitsu EVO (right). They are very similar in design as you can see. The STI makes 300ftlbs vs the EVO 273ftlbs. yet the pressure plate for the STI tests 5% weaker! I haven't heard complaints about the STI clutch... yet.