richmc

Thats why you replace brake fluid by bleeding it through not emptying it and refilling it. I bet the ABS unit comes pre-filled in the factory and they have some high pressure gismo to fill the system.

cat5cable

what are your thoughts re if you have 5.1 and you want to go back to dot 4 ?

ginger

richmc

I guess mop out the master resrvior and get a different colour DOT4 bleed it through, then some more.

Then mayby leave it a couple of weeks and do it again.

markforrester99

Just a small word of warning. I have had the ATE superblue for a while and after a season of trackdays i decided to bleed it through and replaced with RBF600. The blue dye will not flush out of the system. Its a pain in the arse. In hindsight i should of flushed it out with some cheap fluid and then put the RBF600 in it. My reservoir is still blue and i ran alot through it.

Dembo

Why?

They're completely compatible. Nothing to worry about.

richmc

I was thinking if you want to make a complete change, comparisons and all that. I know DOT 4 and 5.1 are compatible whereas 4 & 5 aren't, I'm beginning to think ESP "specials" are no more than 5.1 rebadged. But again we have had ABS and ESP long before a magic ESP grade reared it's expensive head.

martin j

I'll just stick with the DOT 4 then, it only costs me £2odd a litre at work just was curious about the special brew for EPS at £4.

richmc

I checked out the specs (admittedly on wiki) and the temperature specks for ESP are very similar to DOT5.1 so it's just a ploy to get you to buy more expensive fluid. Like Shells big push to try and get everyone to use super unleaded even though there are no gains for most cars.

BenRNBP

I think it's the lower viscosity rather than the temp specs, FWIW the 5.1 in mine seems fine but I always feel I should go back to Honda spec - especially if the ABS was designed to DOT4 specs. Having 5.1 in the clutch helps with the delay valve though so may keep using it in there (or do the CDV removal)

KristianP

When I worked at a Peugeot Dealership, on the later vehicle's, we had to run a program using the diagnostic software to bleed the brake system. It operated the solenoid valves in the pump and you had to run through a sequence of opening and closing the bleed valves on the calipers and pressing the brake pedal.

Not one of my favorite jobs I have to say.