Thanks guys. The only reason I ask, is that I got a litre cheap from a bike shop closing down :-)

Halfords do there own brand 5.1, works out cheaper by the 5 litre, enough to replace the brake fluid in the Passat, the T4, the DD , the 620, toms mito, ellas vespa, and bleed out the clutch of the DD (allways takes alot of fluid to clear this, probably not doing it right?)

pete

Shazzams post is pretty much spot on. The high spec DOT4's usually come out better than 5.1, but for all round performance vs. cost 5.1 takes some beating. Motul DOT5.1 is my regular service fluid and i use it in all brake and clutch systems. Motul RBF600 has now been superceded by 660 which is pretty much a match for SRF but works out about double the cost of the 5.1
One other characteristic of 5.1 is it's thinner than DOT 4 which can help with bleeding, or so i find anyhow.
DON'T use DOT5....as Larry mentions it's silicon based. It doesn't mix with DOT 4 or 5.1 and plays havoc with the seals in Brembo equipment.

Well after a couple of days trying to bleed the rear brake (berlinkin nightmare) ended up with caliper off and upside down before I could get any resistance in the pedal!! but all is good now :D

That's the easiest/best way to do it, and a well know method.
Because the trapped air rises in the fluid, the run of the rear brake line means that the "peak" in the line always holds the air, making it very difficult to bleed.

Taking the caliper off and holding it higher than anything else means that all the air will naturally head in the direction that you are bleeding the fluid.