i know that DOT 5 fluids are, due to thier silicone base, inherently compressilbe (even if mildly). knowing that, would it be okay to use as clutch fluid?? the only reason i ask is because it has a higher boiling point than the DOT 4 that GM recommends so maybe i wouldnt have the flush my cluth hydraulics so often.

 

All depends on if it is compatible with the seals in your clutch system. Last thing you would want is to have that fluid destroy all the seals in the hydraulic system..

 

i doubt it, i have the mcleod master cylinder and the instructions
said not to use DOT5 in the system.

 

I would just use Valvoline SynPower Synthetic DOT 3/4 brake fluid in the clutch system. Its compatible with both DOT 3 and DOT 4, and its synthetic so its less resistant to heat and breakdown, so it should last much longer than conventional fluid.

 

DOT 5 = no no. You could use DOT 5.1 though, which is compatible with DOT 3/4 fluids.

Personally, I use Castrol SRF. High dry boiling point, really high wet boiling point. Not sure if it will eat seals or not, but someone has to try it and find out...

 

x2 dot 5.1 is ok but i think it is too exspensive, i just use dot 4 and bleed the system more often, like every oil change or more if needed.

 

I have been using Valvoline Synpower for yrs with great results.

 

Doesn't GM Make "clutch fluid"? I have heard it is expensive though.

 

exactly right you need to be sure its compatible with dot 3. There are even some dot 4's that are not compatible, those are usually racing fluid that is very high price. Stick only with fluids that are compatible with dot 3.

 

IF I were a rich man...this is what I would use (in the brakes as well)!

 

My brakes still have ATE Super Blue, but it'll be getting the SRF treatment once I get around to deleting my ABS My clutch likes it so far...

 

88958860 GM Brake and Clutch Fluid; Super DOT-4

Its less than $8 a can from the dealer.

 

Is there a reason why more people don't use this?

 

is there a dot3/4 with a really high boiling point since we seem to have issues with fluid boiling in the lines

 

It doesnt really boil in the lines, it boils in the slave, its the closer to the heat source.

 

Shear ignorance I suppose...it has only been recently that I discovered that GM is now using higher boiling point brake fluids in their clutch hydraulics.

 

Its generally easier to get brake fluid from the parts store than the dealer. There are alot more parts stores closer than dealers.

Does anyone know what the boiling point is of the gm brake fluid?

 

Werd. I just got a mcleod street twiin and the master cylinder. The instructions say clearly do not use the 5. It says the 3 has more lubricity.

 

The Valvoline SynPower DOT 3/4 Synthetic that I mentioned before. Synthetics tend to have higher boiling/burn off points than conventional fluids, and its compatible with both DOT 3 and DOT 4, so you can use it regardless of what fluid you have in there now.