BgBoost1

CF,

I wanted to share a fix for a clutch pedal pressure issue that I was having.

About 2 years ago, I started noticing that under 2nd and 3rd gear W.O.T. pulls that my clutch would start "Falling" toward the floor which makes it really hard to successfully make a gear change. Sometimes it would fall about 1/2 of the way, sometimes a little more. It seemed that if I took the side of my shoe and pulled it back up while under throttle it would re-gain the pedal pressure, but not for long. Sometimes when running hard I felt like I was using just my big toe to push the clutch down since it felt like it would only travel about ¾ to 1” before hitting the floor. I spoke to several people and I was told it was the dirty fluid (try the Ranger method Times 100), the clutch, the slave cylinder, the heat from the headers causing the fluid to get hot, etc, etc.

Since the car was putting down over 600rwhp and 565rwtq to the tires I thought that a new clutch and slave cylinder would surely be the correct fix. I was probably pushing the limits of the stock LS7 Clutch anyways although it had never slipped and when removed looked almost perfect. I installed the Katech LS9R Clutch, Slave Cylinder and remote bleeder and thought that all my problems would be over. It didn't change anything…… I spoke to several people and got lots of recommendations on what to do, I tried all the things they told me to, changing fluid, wrapping the lines with expensive silver foil tape, zip tying the lines as far away from the headers, etc and finally I sent Jason at Katech a detailed e-mail on exactly what the car was doing asking for his advice. He had his engineers look at it and they told me that my Master Cylinder was probably defective, and I should replace it with a new GM one. I did some research since I didn't want to replace a defective unit with another defective unit (Since this one failed at only 7,000 miles) and it seemed that Tick Performance had a unit for a little over $320 that utilized a Tilton Master Cylinder and adapter bracket. The Tick MS received many praises from the LS1 Trans Am and Camaro forums, so I wanted to give it a try but found limited C6 Corvette owners using it. I finally found a local guy that had the same issues as I did who replaced his GM Master with the Tick and said it cured all of his problems. He had replaced his clutch 3 times thinking it was clutch issues and finally figured it out his pedal pressure problem by using the Tick.

I spoke to Jason who told me that they had installed them before and they worked great once you had them correctly bled and adjusted, which did take some time. I installed mine about 2 weeks ago and once the system was correctly bled and adjusted it cured 100% of all my clutch pedal pressure problems. Since I have been chasing and throwing money at this issue now for over 2 years I finally feel some relief……..I am really happy that it is working perfectly now!

Many Thanks go out to the forum members who helped me with this issue, the local ZO6 owner (ZO6 Modder) who had the Tick in his car and said it fixed his issues and most importantly Jason at Katech who took the time to help me diagnose the problem….CORRECTLY, and for his instructions on how to properly bleed the clutch hydraulic system. THANKS to all of you!!!!!! I am finally able to enjoy the power that this car is putting down!!!

Crash_Z06

Great you got it fixed!
Thank you for sharing.

Can you post the correct way to bleed the clutch system for the rest of us
?

obzidian

I don't know why this product isn't regularly used or talked about on here. That problem drove me crazy in both of my cars.

Tick has a great kit there and without a doubt it would be one of my first mods.

BgBoost1

Yes, this is word for word from Jason. It worked perfectly!

1. Loosen the bleed screw, remove the reservoir cap 2. Submerge the remote bleeder fitting in the reservoir past the crimp 3. pump the pedal SLOWLY until no bubbles appear, leave the pedal on the floor 4. Tighten the bleed screw, replace reservoir cap 5. Pull the pedal off the floor and pump up. Keep pumping until the pedal height returns to the top

RoHo

Many thanks for posting a fix for the clutch sticking problem.

I have been hesitant on doing a head and cam package thinking it would lead to the dreaded clutch problem, this is encouraging news.

So nice to see some postive input on the Forum for a change.

Carnac

Sounds like a great fix.

I took a look at the Tick web site - they state that the kit only works with 05-08 Corvettes, and that a change in 09 makes them incompatible with 09+ Vettes.

Jim

SmokinZ

This sounds like a nice product to look into!

ByByBMW

THIS!!!! Makes sense. I. like others on this forum, have struggled with the clutch falling to the floor under hard acceleration or not coming back after a hard shift. While I have a great deal of respect for Ranger, I did not personally feel that the "ranger method" of clutch fluid flushing was making any real difference.

This is the first hard proof that there is something else going on in our clutch systems.
Thank you BgBoost1

BgBoost1

Mine is an 07 and it works fine. When I contacted them they said 05-08, but it would not work on the 09 and newer for some reason.



Thanks for posting....I was getting frustrated at everyone telling me to change my clutch fluid and I was getting tired of changing it and still having the same issue. It seems pretty isolated as I run around with 4 of 5 other ZO6's in my town and some of those guys have 40-60K miles and beat on them all the time and their clutch hydraulics work perfectly. Honestly for a while I thought I was going crazy

ByByBMW

No you are not going crazy. I have flushed my master at least 20 times in the last 4 years, AND I only have 8200 miles on my car and almost from the first day, I have had this issue. Flushing the fluid has done NOTHING to alleviate my issues. Normal driving no but if I get on it hard, sometimes the clutch wont come up after to 1-2 shift OR I go for the clutch to shift and find it's almost to the floor, but again only when I am WOT and shifting fast, NOT speed shifting as I lift before each shift.
I am trying to sell my Z, not for this issue but because of an upcoming move but if I have to take it with me, this is the first thing I will do once I get settled.

THANK YOU THANK YOU THANK YOU

Carnac

Yep - miss-typed on my earlier post - works on 05-08, and not on 09+. My mistake - sorry for the confusion...Jim

40YRW8

Thanks for posting. I wonder how many guys out there changed a clutch like you and, still having the problem, removed a perfectly good aftermarket clutch? I also wonder what they used up more, dollars or expletives?
Gary

Unreal

I've had one for awhile. Never had clutch issues before or after.

spdmn75

Just wondering if your master was a little loose after you mounted it to the firewall? It was not as tight as the OEM one after I mounted my TICK.(I did use the rubber grommet)

BgBoost1

This one installed really tight....I would say a bit tigher than the GM OEM Master. If you used the rubber grommet then you installed it correctly. Did you have the clutch pedal box loose or tight when you twisted the master in?

BgBoost1

I personally know of 4 people that I talked with that replaced at least one, and the local guy to me that had a SPEC, BC2 and an LS9R before he found the real problem.

mcar00

Has anyone looked into a heavier clutch return spring for the pedal?

Unreal

I took the return spring off and I've never had an issue.

Carnac

If you are talking about the coiled spring on the pedal arm itself, it is not really a return spring. If it was and you removed it there would be immediate problems.

The spring is actually an over center spring. It starts will a little pressure (to keep the pedal all the way up) and then tension builds about 1/3 of the way through the pedal stroke. Finally, it actually reduces pressure for the final portion of the stroke. It is kind of like the over center cams on a modern compound hunting bow. This reduces the amount of pressure that you have to apply while stopped and are holding the pedal down.

Many have found that removing the spring makes the clutch feel better to them. It can be easier to smoothly release it from a stop with the spring removed. However, GM states that with the spring removed, there is a possibility that the clutch pedal will not fully return to the full up position (just the very last bit at the top of the stroke) and that can cause pressure to build up (because there is a pressure relief function when the pedal is all the way up) and some problems can occur.

For a while it was popular to replace the OEM C6 spring with an lighter OEM C5 spring. I did this in my C6 coupe and found the clutch action was a little smoother. I haven't swapped the one in my 08 Z06.

The springs are prone to breakage and are often not replaced with no problems or a C5 spring substituted. The C5 spring is only about $12 at the GM parts counter. The install is easy, but can be a bit of a pain due to location under the dash.

The OP's problem was not related to the pedal spring and it sounds like the Tick master cylinder was an excellent solution.

Jim

KLRBEE2

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