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Is dot5 ok to use for the clutch in an 08?

Just Enough

No, DOT 5 is fully synthetic and doesn't mix with DOT 3 and 4 so you end up with little pockets of old DOT 3 and 4 which become totally saturated with moisture. DOT 5 is great stuff, it doesn't absorb water and has a high boiling point but they recommend that you completely clean out (meaning flush with alcohol and dry) any remnants of DOT 3 or 4 before pouring in the 5.

glass slipper

DOT 5 is silicone, not synthetic. There are plenty of DOT 4 synthetic brake fluids compatible with regular brake fluid. But you are correct, DOT 5 doesn't absorb water allowing it to maintain a very high dry and wet boiling point. However, it does absorb air easily requiring frequent bleeding...not good for a street car.

hdeyong

I'm changing all the flex hoses on my '76, and will change all the fluid while I'm at it. It has DOT 3 or 4, and that's what I'm going to put back in, because I plan to change it every couple of years.
But, back in about '98, I completely rebuilt the brakes in my Triumph Spitfire, (don't laugh, it's a fun little car), and put in silicone fluid, after flushing with alcohol and drying it out. It's been there ever since, have never had to add any, it has a hard pedal, it's in the clutch hydraulics too, and have never had any problem of any kind.
I'm thinking the material used in brake components has changed, and if manufacturers don't recommend it, I wouldn't use it.
I'm converting the Triumph to a solid rear axle, and after installing new wheel cylinders, figuring out a flex hose, etc, will have to bleed the brakes. I'll flush the DOT 5 out and go back to 3, and just change it regularly. Why take chances?

pragmatic

Regular DOT 5 is no good you could use DOT 5.1, but it does not get you anything over DOT4 for the clutch. On the clutch I use DOT 4. For the brakes DOT 5.1 which has higher boiling point and lower viscosity has some advantages and is what I use.