306oc - Peugeot 306 Owners Club & Forum

Full Version: Brake fluid info
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Just wondering a few things, i'll be changing my calipers over this weekend and wondering about fluids. (also to add to the OC database.

1 - how much fluid is in the brake system (average)
2 - roughly how much am i going to loose when changing the calipers (hoses will stay on)
3 - what fluid should i use to top up, standard DOT4 or high performance 5.1?
4 - is there any major difference in fluid?
5 - can the fluids be mixed; if DOT4 is already in the system, can i top up with 5.1, or would the entire system need emptied adn refilling
ginge191 Wrote:Just wondering a few things, i'll be changing my calipers over this weekend and wondering about fluids. (also to add to the OC database.

1 - how much fluid is in the brake system (average)
2 - roughly how much am i going to loose when changing the calipers (hoses will stay on)
3 - what fluid should i use to top up, standard DOT4 or high performance 5.1?
4 - is there any major difference in fluid?
5 - can the fluids be mixed; if DOT4 is already in the system, can i top up with 5.1, or would the entire system need emptied adn refilling


1- around 1 litre
2- id be draining as much as i can
3- personal choice, dot4 is fine for road use
4- yes, higher boiling points etc
5- No they cannot be mixed!
ginge191 Wrote:Just wondering a few things, i'll be changing my calipers over this weekend and wondering about fluids. (also to add to the OC database.

1 - how much fluid is in the brake system (average)
2 - roughly how much am i going to loose when changing the calipers (hoses will stay on)
3 - what fluid should i use to top up, standard DOT4 or high performance 5.1?
4 - is there any major difference in fluid?
5 - can the fluids be mixed; if DOT4 is already in the system, can i top up with 5.1, or would the entire system need emptied adn refilling


1. not sure
2. not much if you put the flexies hanging up and a cap on the end - it will stain tarmac etc if in contact
3. i used DOT4
4. not sure
5. never mix as they have different boiling points
Also Ginge i'd look at getting braided hoses, about £30 odd. My rear flexi's were not in good shape
Anton Wrote:Also Ginge i'd look at getting braided hoses, about £30 odd. My rear flexi's were not in good shape

I've just had brand new ones put on for it to pass it's MOT - i've got braided on the rear - theres no point in me putting on braided on front when they're brand new standards. If i get some spare cash i'll look at replacing them.

saying that, the garage changed the hoses, and it seems i have braking on one side of the car.. not the other; harsh braking and i turn to the right Doh

soon find out anywho

cheers for the info peeps!
Invest in an easi bleed system makes bleeding brakes easy as pie! I changed the front breaks on the front of the car including 2 complete new brake lines used a 1litre of 5.1 to flush the system complete bled the whole system in less than 10 mins and that was doing it twice.
All normal fluids - DOT4, DOT4+, DOT5.1 can be mixed.

DOT5 can't. It's silicone based.
note; some dot4 stuff is silicone based-----------------i fitted a caliper on a celica in work and was sent a litre of dot4 in a yellow container (not comma) and that was silicone.

same day one the lads i work with brought his wifes focus in that has popped a front flexi when she tried to do an emergency stop at a crossroads !!!! fitted a hose and changed all the fluid through all 4 corners.
DOT4 by definition is glycol based....you can tell immediately if it's silicone anyway (dot 5)