Hydraulic Clutch Fluid

[bb62]

1. Why is the hydraulic clutch fluid different than brake fluid?
2. Can I use DOT3 brake fluid in the clutch master cylinder? The GM manual note "Hydraulic Clutch Fluid (GM Part No. 12345347 or equivalent)". I know that Paul's write-up in Heart of the Beast Issue 48 shows DOT3, but that is not what the 95 FSM states.
3. Does anyone know the clutch/slave hydraulic fluid capacity? The 1995 GM shop manual for the Corvette does NOT have a listed capacity (neither does the operations manual in the glove box). This seems unbelievable to me.

[Neat]

It would probably be more accurate to say that brake fluid is not different from hydraulic clutch fluid, but your reasoning stands. The fluid (regardless of name) is being used to transfer force from one sealed cylinder to another. That's true in the braking and in the clutch system.

Your best option (as far as I know) for clutch fluid is Valvoline DOT 3 & 4 synthetic brake fluid. Any DOT 3 brake fluid would work in terms of operating the system, but as I understand it, the Valvoline 3/4 synthetic fluid is the most gentle / compatible with the seals in the clutch master and slave cylinders.

The capacity is less than a pint. I'm not sure how much, but 3-5 oz. is my guess. You'll need more if you plan to flush / bleed the system.