chb88

It getting really boring replacing the slave cylinder in my 94, Its the 3rd one in 2 years. The last one was from the General and it lasted a total of 13 months. The revisior is completely black which I believe is a deterorated seal, true of false. Any others want to chime in with there experiences with this system, feel free.
Also they must be designed to only fail during the rainy season....who can figure.

grandspt

Changed my slave (second time) and master cyl. (1st time). Car is a 1996 with 26,000 miles.
Fluid was black, second slave was leaking badly!
I store the car in the garage for our New England winters
This time I used silicone brake fluid Dot 5 in the hydraulics.
The clutch take up seems better with the dot 5 fluid. But I do notice a slight clicking noise from the master cylinder, nothing major (it is probably because the GM fluid has different additives in it).
I did this 2 months ago so it's still too early to tell if it cures the problems of continual failure.
My theory is that the hydroscopic nature of basically brake fluid was getting moisture in the system. The first Slave unit had tiny rust spots in the bore! But what do I know?

FELNGR8

After both a slave and master replacement I was advised to use only the GM fluid, which I bought for future refills. It does have additives that address problem noise in the master cylinder. It occurs to me that additives that reduce noise may also reduce wear?

Should everyone be using straight brake fluid when the General says otherwise?

grandspt

Well,I was using the original GM stuff (don't have the part # on me right now, but I got the part # from the shop manual). I figured if the parts were wearing with the original hydraulic fluid then what do I have to lose using Dot 5?

FELNGR8

The general did have a bad run of slaves in stock, but I haven't heard of bad master cylinders in stock. I had to replace my master after 4 years and 40000 miles of driving. I hope that isn't normal wear, but it could depend on how you drive. I.E., I seek out places where I have to shift the gears a lot.

Only time will tell if using the GM fluid makes a difference.

chb88

I thought I found the issue with the defective slaves, namely the saw tooth washer comes loose and ultimately the fluid leaks out. With the current slave I was sure this washer was completly seated correctly before install. This one made it about 8K miles, just out of warranty and double the previous results. I will give the GM fluid a try if the forum concensis is that positive. I'm struggling with believing there is much of a differance. Hell I bleed the brakes last fall, when I did the slave on the clutch, and that fluid is still clear and its the same fluid.

Atok

False. The fluid will turn black eventually. My '95's fluid has been black forever. A completely flushed and changed the fluid 2 years ago. Refilled from a new bottle of the GM recommended fluid. It turned black in a few months - no leaks and the clutch works perfectly.

If it's not leaking and it still disengages the clutch, it's fine.