I am going to be replacing my brake fluid as part of installing new pads and steel lines. I am going to use either Motul 600 or Superblue. What I want to know is, is it safe to mix this with the factory DOT 3 stuff that's in there now? I'm pretty sure there's an issue mixing DOT3/4 with DOT5, but what about mixing synthetic stuff during replacement.

 

When I switched to ATE blue, I flushed the system by bleeding a bunch from each wheel. No problem, on a couple different cars. I don't think I'd mix them by simply topping up the reservoir, but it sounds like you're gonna flush it anyway.

 

I am going to use the technique described in the Team Integra Brake Flushing article.

Thanks

 

Its perfectly safe to mix any dot approved brake fluid but bear in mind if you mix dot 3 and 4 the fluid will not be as good as just using dot 4.

As far as synthetic fluids go, if you want to use them it is a good idea to clean as much of the old stuff out as you can by bleeding the brakes through with Methylated spirit. Then put the new fluid in.

 

I've never seen anyone recommend cleaning like that. If my take on this is right you're talking about isopropyl, or rubbing, alcohol.

Wouldn't think dry out rubber components?

What would the procedure for that type of cleaning be?

 

Hi Konali! Yes rubbing alcohol. (You say tomato I say tomAto!)
Best procedure is to use one of those pressure brake bleeders that runs off your spare wheel pressure. Fill the refil bottle with the alcohol then connect it up. Then bleed the brakes in the normal sequence.(I usually start at the back right wheel and work clockwise on Hondas). Carry out this procedure until you have used 2 refill bottles full (about a litre/2 pints) Then fill the refill bottle up with your new brake fluid and bleed through until you have no bubbles. Easy! I have carried out this procedure many times and not had any bother. My own car has completed 40,000 miles since I changed its fluid. The alcohol only dries out the rubber if it is left to dry. If you have the system filled with the alcohol then brake fluid it wont get the chance to dry out. Hope this helps.

 

You sure you wanna use Motul 600? Unless this is for ur race car, I don't think that they suggest you use this brake fluid.

http://www.inlinefour.com/motbrakfluid.html

 

To be perfectly honest with you, no, I'm not sure, and that's why I'm asking questions.

It would only be used for 1-2 Auto-X/mo and a few HPDE track days/yr. My prefered driving style is heavy/late braking, so I don't want to overheat the pads, Hawk HPS and or HPS+.

I wasn't aware of the MOTUL DOT 5.1. I also figured for the small $$ difference, the increased heat range would be better.

Is there a really downside to using the RBF600 on a car driver 80%+ on the street aside from unnecessary cost?

 

Generally (not always) the higher-boiling-point stuff absorbs moisture more quickly. So if you want to always make a habit of flushing it, good for you.

Someone who maybe waits 2 or 3 years between brake-fluid flushes, maybe better off using DOT3. Someone who flushes their brake fluid before every race isn't gonna care that it takes up moisture a little faster.

 

You cannot mix DOT 3-4 with DOT5 Put some in a container, equal amounts of both and watch it jell up in a few hrs. If your gonna use DOT 5 make sure you get all the other shit out.