DOT 4 fluid recommendation

[moze229]

Ok all, this is going to get real remedial here, so bear with me. This is for a 2004 R1100S.

The local auto parts stores both carry Valvoline synthetic DOT 3-4 brake fluid. Is this OK to use? How is DOT synthetic 3-4 different from DOT4? (I know it will have to do with the boiling point, but what gives here?)

Then I got really confused because I thought, "Well, it would be nice to have a fluid of a different color so that it would be easier for me to see when all the fluid has been flushed." So I stumbled upon ATE's DOT 4 fluids that come in blue or gold colors. Alas, they are not synthetic.

So I have DOT 3-4 and DOT 4, synthetic or non synthetic. Then there is the factor of fluid color which may or may not be approved for use on the road because of the color. I need someone to point me in the right direction. HELP!

BTW - looking for fluid to do brakes and clutch

Matt

[markjenn]

The Valvoline stuff is well-liked and widely used. It will work fine.

Sometimes they call it DOT3-4 because DOT4 is a superset of DOT3, therefore, by definition, a DOT4 fluid is automatically a DOT3 fluid. You can use DOT4 anywhere DOT3 or DOT4 is specified. For that matter, you could use a DOT3 where DOT4 is specified and it would work Okay but you wouldn't have the same margins with respect to boiling point and the like.

Synthetic vs. non-synthetic? I honestly don't know what makes a brake fluid "synthetic". I wouldn't worry about it.

Different color fluids are just mfgs trying to differentiate their products. I wouldn't worry about this either, although I suppose it would assist in knowing when you've bleed the system completely. I can usually tell pretty easily - the old fluid tends to have a cloudier appearance.

- Mark

[moze229]

Thanks Mark. Well, I guess that clears that up then.

Matt

[Dr. Curve]

I have run Dot 5.2 in the BMWs for the past ten years and really like it. The difference between it and the fewer dot (3or4) fluids is that it has a much higher boiling point, is NOT silicon based, and is highly resistant to water absorption as compared to ANY dot 4 fluid. (unless its a silicon based one, which throws ABS systems off and is only slightly less hydroscopic than 5.2)