Clutch fluid replacement

[vilant]

The original GM P/N 12345347 fluid is apparently hard to find. I found it listed on Amazon a few months ago, but the shipping date kept getting pushed back until they out right canceled it. I've seen you can use DOT 3 brake fluid, but it's missing additives, which can cause squealing. I need to change my fluid, what is the best replacement fluid? Or does anyone know where I can buy the original #12345347 (I already checked Jerry's, White's, Ebay, and Amazon)?:cheers:

[XfireZ51]

I just changed mine w Dot4 Prestone hydraulic fluid.

[mike100]

... I've seen you can use DOT 3 brake fluid, but it's missing additives, which can cause squealing. ...

First time I ever heard of that- what exactly would squeal?. Parts store DOT 3 works fine, especially since the clutch circuit doesn't run too hot anyhow.

[vilant]

Well it only happens every once in a while. At first I thought it was the power steering, but then I noticed when I held the clutch pedal down longer than usual it would make a light squealing sound. The original fluid is probably still in there. When I googled the part #, a link to CF came up. The thread talked about the clutch fluid and how some still experienced squealing when replaced with the DOT 3. Apparently the additives in the original are what help stop the squealing(at least that's what I got out of it).
Just got a tip to try the dealerships and if it's not there, there's a place not too far from me that should. If I can't track down the original, I'll go with the DOT 4. :cheers:

[mike100]

DOT3 can take higher percentage of water contamination, DOT4 has a higher boiling point, but should be changed more often. I know my C6 specs DOT4 for the clutch slave, but i use DOT3 in my C4 because I had a lot of it around the house. It works great- mainly having new, clean fluid is a plus. A pint of DOT4 is cheap- consider it a flush fluid in case you ever find the GM stuff.

[XfireZ51]

I have DOT4 around so use it. Check the clutch fluid every several thousand miles and using Ranger's method of keeping the fluid clean, it makes it easier to keep the fluid fresh.

[TheBlackPearl]

Where is Ranger's method, i can't seem to find it. Also how much fluid do you usually use up when changing? I'm gonna bleed the brakes and clutch and plan on using Motul 600 but I need to know how much to buy.

[XfireZ51]

Where is Ranger's method, i can't seem to find it. Also how much fluid do you usually use up when changing? I'm gonna bleed the brakes and clutch and plan on using Motul 600 but I need to know how much to buy.

I've been using this methodology for the last several years. Getting the fluid clean the first time is the longest maintenance. If you check the fluid on a regular basis and change before/after race conditions, it gets easier. Beats getting under the car, drain and fill. This way you get dust out of system by mixing the fluid and continuing to flush out the particles.

http://youtu.be/gBbsy0LjUvE

[Kevin]

First time I ever heard of that- what exactly would squeal?. Parts store DOT 3 works fine, especially since the clutch circuit doesn't run too hot anyhow.

i used dot3 once and when I slipped the clutch to get up the driveway and over the lip into the garage the clutch would squeal. sucked it out and replaced with clutch fluid

[TheBlackPearl]

Wow, that's great and easy. I don't suppose Ranger's method could also be used for the brake fluid?

[mike100]

Wow, that's great and easy. I don't suppose Ranger's method could also be used for the brake fluid?

It could be, but it would probably cost too much since the siphon transfusion method does waste some percentage of the new fluid. Brake reservoirs are pretty big if you think about it. A conventional bleed is best since it purges the calipers of older fluid.

[TheBlackPearl]

Yeah that's what i'll do, bought a case of Motul.

[Paul Workman]

Squeal?? I'm still :icon_scra to understand how/what would cause the clutch to squeal, depending on hydraulic fluid. Are we talking about sqeaking hydraulics as the peddle is pressed in and out?? If not that and you're referring to some squeal from the clutch itself, e.g., the fluid is getting out of the slave and on the friction disc...maybe...but that would be another issue entirely.

Sorry to be so obtuse.:o

[Paul Workman]

Yeah that's what i'll do, bought a case of Motul.

Just a thought:

Maybe the best way to purge the clutch system is to remove the slave cylinder, open the bleeder valve, and force the actuator rod into the cylinder. This will instantly purge about 90%+ the contents of the cylinder - where the contaminated fluid resides. Then, placing a finger over the bleeder valve, and allowing the slave piston/actuator to relax will pull fresh fluid into the slave without introducing air into the system, if done carefully to avoid it.

I don't recall if the exhaust has to be removed to access the slave - but if the exhaust manifold is removed, e.g., to do a header install, that would be an excellent time to purge the clutch system. After that, normal maintenance is all that is needed. Saves a LOT of time and wasted fluid that way!