changing from DOT 4 to DOT 5.1 question

[Strettman]

hi, i know this is probabaly a silly question but i couldn't find anything on the whole of the interwebs with an answer. tomorrow i might change my brake fluid and i plan to use DOT 5.1 instead of DOT 4, i will be using a pressure bleeder if i can get my hands on one (probably the gunson ezibleed). my question is, do i need to get all of the DOT 4 out of the brake lines before i start putting in DOT5.1? sorry if this is a really stupid question, i bleed brakes quite often at work but i have always used DOT 4 so i don't know what you are suppose to do when changing to DOT 5.1. i'm only interested in using DOT 5.1 because i am thinking of maybe starting on track days and it would just be abit of a bonus and i can also get it for a couple of quid more per litre than DOT 4.

thanks

 

[BIGASH]

Yes you would need to drain the system and then i’d flush a fair bit through but I much prefer to run just a higher quality DOT 4 fluid myself. Something like the Motul RBF600 is normally plenty good enough for the clio’s with a much higher wet and dry boiling point than std DOT 4

 

[MartinR]

As BIGASH said just use a good quality dot 4 fluid.

ATE super blue gets my vote

 

[sbridgey]

I used to use the Carbon Lorraine Dot 4, that survived my driving style so must be pretty good!

 

[Strettman]

thanks for the replies, i may just stick to DOT 4 to save some hassle. i will decide tomorrow before i do it.

thanks for the help

 

[MartinR]

Must be good if Si used it lol. probably boiled/set fire to everything else lol