kadeer

Hi guys,

I am not sure what brake fluid in the car, if I topped with 'Super Blue' Brake Fluid, would that cause any problem if it is not the same.
Thanks
-Kadeer

graham_mitchell

Are you topping up the reservoir, or flushing out the system?

DOT 3, DOT 4, and DOT 5.1 are all similar brake fluids; they all have glycol/borate ester bases, and can be mixed together. DOT 3 will harm natural rubber seals and that can be an issue in some brake systems. If you add DOT 4 fluid to a DOT 3 system, the resulting fluid boiling point will be lower than that of DOT 4. Most conventional brake fluids are clear to golden in color.

DOT 5, because of its silicone formulation, it is entirely different than the other brake fluids, and is only compatible with itself. Silicone based brake fluid is violet or purple in color.

DOT 5.1 is relatively new. It is not silicone based. It is borate ester based. Whoever decided to call it 5.1 didn't do us any favors. The 5.1 designation leads people to believe it is a form of DOT 5. It's not. It's completely different stuff. DOT 5.1 should not be mixed with DOT 5.

If DOT 5 silicone fluid is combined with any of the other brake fluids, the silicone may react to existing contaminates in the system and form a gel like substance that stops up the brake passages, sticks pistons, and totally screws up the brakes. The cure for cross-contaminated systems is a complete brake system disassembly, cleaning, and re-build.

Hope this helps,

Graham

STLPCA

kadeer
Yes, you can use Super Blue to top up your reservoir. However, it will tint your fluid blue making it difficult/impossible to determine fluid degradation from a darkening of the otherwise gold color. That's why production of SB has been discontinued. Make sure you do a flush at least every 2 yrs. If you're unsure of current age, I'd flush the system to have a good starting point.

914und993

Dan, are you sure ATE Super Blue has been discontinued? It seems to be readily available from multiple sources at the normal prices.

Chip

Bill Gregory

Steve Weiner and others have said it's no longer being imported into the US. Doesn't mean existing stocks aren't being sold, which is probably what you're seeing. With ATE Type 200 being available, which is the same fluid minus the dye, I'd be surprised to see much, if any, price increase on existing Super Blue stocks.

STLPCA

[quote]Originally posted by 914und993:
<strong>Dan, are you sure ATE Super Blue has been discontinued? It seems to be readily available from multiple sources at the normal prices. Chip</strong><hr></blockquote>

Chip
Yes. It has been discontinued, although as Bill said inventory apparently remains plentiful (not to mention the 4 cans on my shelf left from a group case purchase). The <a href="http://www.conti-online.com/generator/www/com/en/ate/ate/themes/products/brake_fluid_en.html" target="_blank">ATE website</a> no longer lists Super Blue. I had read months ago that ATE was to have introduced a new DOT 5.1 (non silicone - see graham's thorough explanations above) higher performance fluid by now, but haven't heard anything more.

Anir

Graham,

Thank you for the wonderful summary.

kadeer

Thanks Guys,
From Grahams and Dans comments, I will top it up with dot4 gold brake fluid.
-Kadeer

Robert Linton

As I read the original post, Kadeer is not sure what fluid is in his system. As such, and given (1) this is a critical safety component and (2) the cost of new brake fluid is so minimal, would it not be better to flush the system and put in entirely new and definitely compatible fluid?

STLPCA

Robert
I agree w/you & were it my car, I'd flush the system to be sure of age & fluid quality. That would certainly be the prudent course. However, Kadeer's question was compatibility. ATE 200 or Blue can be mixed w/whatever conventional brake fluid he has.