[Z06] Clutch question, slippy 3 to 4 shift
Thread Starter
Instructor
Joined: Aug 2010
Posts: 131
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From: Seminole Texas
Clutch question, slippy 3 to 4 shift
I've searched and really can't find the answer I need. I bought a used 02 Z06, 51,000 miles, one owner, from a used car dealer in MO. Everything feels great, looks great. I've changed trans fluid and axle fluid to Royal Purple fluids, old fluid looked really good. I've done a few clutch fluid changes to Dot 4 fluid, the old fluid didn't look too bad, it was black and had stuff stuck to the sides, but not too bad for 51,000 miles.
Now to my question, if I'm cruising at road speed, downshift to 3rd and go WOT, when I go to 4th the clutch feels soft and slippy. But, if I launch out in 1st at WOT, roll through the gears, when I hit 4th it feels solid. Back to back WOT runs, clutch feels solid. Feels like it needs some heat before it grabs solid. So, is it normal? Hydraulics or clutch?
Now to my question, if I'm cruising at road speed, downshift to 3rd and go WOT, when I go to 4th the clutch feels soft and slippy. But, if I launch out in 1st at WOT, roll through the gears, when I hit 4th it feels solid. Back to back WOT runs, clutch feels solid. Feels like it needs some heat before it grabs solid. So, is it normal? Hydraulics or clutch?
Race Director
Joined: Aug 2000
Posts: 10,649
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From: Central Florida
I've searched and really can't find the answer I need. I bought a used 02 Z06, 51,000 miles, one owner, from a used car dealer in MO....I've done a few clutch fluid changes to Dot 4 fluid, the old fluid didn't look too bad, it was black and had stuff stuck to the sides, but not too bad for 51,000 miles....
Ranger
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Joined: Aug 2010
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From: Seminole Texas
Reading and searching is the main reason I started changing clutch fluid, thanks Ranger! I've got one 12 once can through it so far. The fluid doesn't turn dark unless I beat on the car, which is pretty rare. Peddle has never gotten stuck, or failed to disengage clutch. Car runs perfect and is bone stock. Just trying to get an idea about future car expenses, whether the clutch is on it's way out, or is just fine. I'll keep doing what I'm doing, driving and enjoying the crap out of this car. 
Race Director
Joined: Aug 2000
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From: Central Florida
Swayze,
I'd stick with my recommendation in post #2. Two more cans of fluid ($5.00 investment). 50K miles will embed clutch dust in every eddy within the hydraulics. The goal is to dislodge all of it via the cleansing power of fresh fluid coursing by to bring crud into suspension and then into the reservoir.
At stock power levels, the LS6 clutch should not change feel once the fluid is really clean and fresh.
Good luck.
Ranger
I'd stick with my recommendation in post #2. Two more cans of fluid ($5.00 investment). 50K miles will embed clutch dust in every eddy within the hydraulics. The goal is to dislodge all of it via the cleansing power of fresh fluid coursing by to bring crud into suspension and then into the reservoir.
At stock power levels, the LS6 clutch should not change feel once the fluid is really clean and fresh.
Good luck.
Ranger
Thread Starter
Instructor
Joined: Aug 2010
Posts: 131
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From: Seminole Texas
I changed the heck out of the fluid, no help, getting worse. Bought a new master clutch cylinder from Gene, latest part number, fixed. Even shifts better now, I guess clutch wasn't releasing all the way, should have changed it sooner.
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Joined: Sep 2005
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From: Pasco WA
Be very happy if that's the end of it. GL.
Thread Starter
Instructor
Joined: Aug 2010
Posts: 131
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From: Seminole Texas
I'm sure it'll always be something. But hopefully it won't be to bad since I'm keeping this thing stock. I learned my lesson on my 97 Dodge Cummins diesel, ran 11.86 at 114.1, fun but so much work.
But hopefully it won't be to bad since I'm keeping this thing stock. I learned my lesson on my 97 Dodge Cummins diesel, ran 11.86 at 114.1, fun but so much work.
Race Director
Joined: Aug 2000
Posts: 10,649
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From: Central Florida
This simple maintenance task should be a routine preventative step for owners of all Corvette with manual trannies.
I'm now on my 3d Z06 with 100K street miles and 773 burnouts and passes down the 1320' with zero clutch pedal issues.
Ranger
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Race Director
Joined: Aug 2000
Posts: 10,649
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From: Central Florida
You can make the switch gradually by simply using DOT4 every time you swap the content of the reservoir. C5 reservoir holds 2 ounces. The entire hydraulic including reservoir, master and actuator (slave) holds less than 6 ounces. So every swap will increase the percentage of DOT4 in the system.
Ranger
