Clutch fluid dot 4 or 5.1

[hodge]

Would there be any advantage to using 5.1 fluid for my clutch.

I know there's a huge difference when swapping dot 4 for 5.1 in the braking system, but is it worth it in the clutch lines.

 

Thanks

John

[chrispot]

there would no advantage in using dot 5.1 over dot 4, as you may be aware dot 5.1 has a higher boiling point, dry and wet (3% water content). there is only about 40 degres difference between dot 4 and dot 5.1.

if it were my car i would just buy dot 5.1 for the brakes and use the same for the clutch, brake fluid should be changed every 2 years regardless of mileage.

[hodge]

I'll use 5.1 then if its got a higher boiling point seems I'm running a 4.5 inch downpipe and it's pretty close to the master cylinder.

[Paul Whiffin]

Motul RBF660 is what we use on track cars.

[Dnk]

Motul RBF660 is what we use on track cars.

 

[Chris Wilson]

Anything, no need for something exotic unless the slave cylinder is near a source of extreme heat, and then you would be far better of insulating it. Clutch fluid is under no duress at all.

[garethr]

If the high temperature performance isn't needed you might be better off with DOT 3 because, IIRC, DOT 4 and 5.1 are more hygroscopic and would have to be changed more frequently.

[hodge]

Anything, no need for something exotic unless the slave cylinder is near a source of extreme heat, and then you would be far better of insulating it. Clutch fluid is under no duress at all.

 

Thanks Chris. I've just stuck some DOT 4 in. It's just what I had lying around in the shed.

[Chris Wilson]

Thanks Chris. I've just stuck some DOT 4 in. It's just what I had lying around in the shed.

That's fine, no need to waste expensive fluid on most clutches