Has anyone had experience with DOT 5.1 brake fluid. I found a link speaking of the differences between DOT 3 vs 4 vs 5 vs 5.1 here but has anyone had personal experience?

I'm taking off the front and rear calipers and I figure now would be a good time to replace the fluid.

Also, ideas on how to cycle the ABS pump during the procedure?

 

Any downsides of DOT 5.1?

 

None from what I've read, hence the question.


Its harder to find (not at Walmart), its glycol-based (still absorbs some water), and more expensive than DOT 4. But I believe its used in "prancing horse" and "raging bull" marques.

 

Is it THX certified?

 

Does this mean that DSC/ABS is 'surround braking'?

 

Everything you need to know about brake fluid...

http://www.stoptech.com/whitepapers/brakefluid1a.htm

5.1 is fine, but way more expensive than something like Ate Blue or Motul 600... It's even more than Castrol SRF, I think, isn't it? A good fluid like Ate Blue or Motul 600 will work just fine...

There's no need to cycle the ABS pump - just get a Power Bleeder, fill the reservoir, and flush!

 

Ditto on the ate Blue.

Jim

 

Keep in mind as you spend the slush fund that there is no outright performance gain in brake fluids. Only operating temperature compliance.

If you are not boiling the current fluid then there is no need for alternative fluid. I'm not suggesting that fluid be ignored for years and be considered on par with some of the upper grade or even stock fluid. Only that sometimes folks are lead to belive that they 'need' exotic fluids when in fact they won't benefit from them. Some high temp fluids may in fact become less effective over time due to mousiture and have a lower wet bp than what you have now. That's just not good.

The ST data is nice but if you do a search you'll find that there are extensive lists compiled by folks listing the exact dry and wet boiling points of dozens of fluids on the market. In fact there are quite a few with good numbers that don't cost an arm and a leg.

Giving a nod to any of the aftermarket BBKs out today you may well find that the need for 'high end' fluid is much less. Not more. This simply due to the better cooling properties of the parts than the stock ones.

 

Silicone-based fluid is a no-no in a daily driven car with ABS I was told. Not only is the fluid not compatible with internal seals in the pumps (it eats it), but it can slip by seals and does some kind of hydro-compession-aeriation thingy (yes, that's a technical term). Anyone else heard of such a thing(y)?

I thought, while more expensive (maybe $20), it might be worth the extra measure of robustness.

 

Yes much of that is correct. I can't speak on the scientific aspects but what it means is that it is compressable. Not really a good thing for high pressure applications and pedal feel. Show cars and bike use this as it does not hurt paint if spilled. Tried it one time in a formula car....poor feel. Went back.