First off I'm not selling one over the other. But I ask myself, which one is the best brake fluid? What is the difference between them? Well I started comparing them and I found it a pain in the as* to make an objective decision looking at data sheets. So I decided to make an Excel file and write down all the info I can find on the manufacturer's websites to be able to compare them side to side. Then I sorted them by wet boiling point and viscocity to decide which one was the better one (in numbers, I'm walking on thin ice don't want to get everybody riled up with another oil thread ).

Here is the link to the table:

Automotive technology: Brake Fluid comparison table

Something I found doing all this research, is that the better fluids were much better at placing all the information and were much more direct an objective at it. The fluids with the "worst" numbers were somewhat hidden and hard to find. Even the links to the data sheets were hard to find, and they have to provide it by law. Any input? something I missed?

 

As far as the actual choice of brake fluid is concerned, the specifications for the
originally specified "ITT Super DOT 4" lead me to believe that closest substitutes
are the Low Viscosity DOT 4 offerings from ATE, Pentosin and Motul.

The low viscosity is the key differentiating feature. It is directed at the needs
of ABS systems for rapid cycling through small orifices.

I prefer the ATE simply because it still comes in a metal can.

++

 

Yes that's s true! You want lower viscosity on your car to make the ABS more responsive, since the ABS uses motors that pulse the caliper's piston on an off at relatively fast rate. And that's the problem with using brake fluids rated at 5.1. They are compatible with DOT 3 and 4, but their viscosity rating is lower (i.e. the fluid is thicker) making (theoretically) the ABS less responsive. This is all very subjective because to compare you would need to test the ABS and who wants to do that?! But I agree, ATE and MOTUL are the better ones. I prefer Motul, just because I'm loyal to their oils, but when you drive a high performance car (like an S-type R for example) you want a fluid that is up the list, or you might get brake fade (if you take your cat to the limits that is ).

But all I wanted was to put all the numbers together and see the results.

 

You sell Motul don't you?

The list on your site is not very complete. It omits a lot of well known names
such as Pentosin.

I distrust comparisons that use cherry picked and incomplete data.

Furthermore this statement on that page is completely wrong:

Oh, I see ... your page is filled with affiliate links to amazon.com

Those links which one would assume to be links to the specification sheets
are no more than affiliate links on a site that you control. Not cool.

++

 

You're suggesting that there are some products that despite meeting Jag's spec of DOT 4 fluid, may induce brake fade?

This seems to suggest that you know something that Jag does not. Care to share?

Another mention is made about DOT 5.1 fluids inhibiting the effectiveness of ABS due to higher viscosity. To make such a statement with any sort of credibility would requires intimate knowledge of the precise system design parameters, specifically at what level fluid viscosity would indeed become critical.

Do you have such knowledge or are you just making this stuff up, similar to previous posts on 'best maintenance practices'.

I'd suggest discontinuing your sideline of crackpot theories before your employer finds out and decides it reflects badly upon his business.

 

I dont sell Motul... but you are right about missing pentosin. Any other brands that are not there that come to mind? I'll add them. The blank spaces are because I couldn't find that particular specification. But including a link to the spec sheet is a great idea, i'll get to it.

 

IIRC, the Jaguar specification for our X350 is "Super DOT 4," and I found Pentosin Super DOT 4 (in metal cans) at both O'Reilly and Advance.

 

Nice information but missing a gold standard of brake fluids, . That's what most of the race teams are using.