Dave 20vT

Active Member
Mar 15, 2010
29
0
Stevenage
Is it possible to replace the Ibiza MK4 Dot 4 fluid for 5.1 without causing any problems?

I currently use Motul RBF600 (Dot 4), and was looking into swapping onto 5.1 brake fluid (RBF660), but I am unsure if the different fluid is compatable with the MK4 brake system. I do a few trackdays every year, and have used this same brand of Dot 4 brake fluid in a few cars now, and I am wondering if a change to quality 5.1 will improve the durability of the brakes.

My car is a 2004 PD130 FR, with S3 front calipers and standard rears.

Also, can anyone tell me how much fluid I will need for a full bleed?

Thanks!
 
RBF660 is Dot 4 but with a higher boiling point than your RBF600. I think it's in fact higher than a lot of Dot 5.1 stuff
 
I thought DOT4 and 5.1 were interchangeable, but that you would have problems if you put DOT5 in instead of 4? doesn't 660 absorb fluid more readily so requires changing more often?
 
They are interchangeable, but as mentioned some dot 4 is better than 5.1. Personally i'd stick with dot 4 and go for the next motul in the series.
 
Just ordered my RBF660 which I didnt realise at first was also a Dot 4, like the RBF600. I am hoping for a couple more track days this year, where I will get chance to see if it is even more fade resistant than than the 600 which I having been using in various cars for a few years now.
 
RBF600/660 are both what I'm looking into and is what seems to be what most people recommend. Will this be the best thing to go for? How often will I need to replace it though?

Cheers :).
 
I am getting my fluid swapped today having had RBF600 in the car for about 8 months. In road driving this fluid doesnt offer any different feel to the standard fluid, (my opinion), however if you going to pushing on quite hard or doing track work this fluid, particularly in combination with the right brake setup is in a different league.

I am changing fluid out of good habit, as I want to try and do a couple more trackdays this year, using the slightly higher rated RBF660. The fluid that is getting drained today still felt perferctly good, and as I say I am only swapping out of good practice.

IF you using these fluids, I think you need to use judgement on the feel of the brake pedal. My mate is still using RBF600 that's been in his car for 18 months, as he says the brakes are spot on, and he doesnt do the trackdays. All opinions of course.
 
I am getting my fluid swapped today having had RBF600 in the car for about 8 months. In road driving this fluid doesnt offer any different feel to the standard fluid, (my opinion), however if you going to pushing on quite hard or doing track work this fluid, particularly in combination with the right brake setup is in a different league.

I am changing fluid out of good habit, as I want to try and do a couple more trackdays this year, using the slightly higher rated RBF660. The fluid that is getting drained today still felt perferctly good, and as I say I am only swapping out of good practice.

IF you using these fluids, I think you need to use judgement on the feel of the brake pedal. My mate is still using RBF600 that's been in his car for 18 months, as he says the brakes are spot on, and he doesnt do the trackdays. All opinions of course.

Dave can I ask how long your RBF600 has been in your car? :). Let us know what the 660 is like!
 
The 600 was in for 8 months, and the brakes still feel spot on. I will update the thread once I have a decent go with the new fluid, however I don't really expect any day to day difference, only once on track do you appreciate how good this fluid is..
 
Thanks Dave! Also how many litres will the system take? (Having never replaced brake fluid in the car).

I suspect 600 won't last as long 660 but suppose it is a question that only time can answer!