Brake fluid quality

Time to flush my brakes and clutch. I get that there is DOT 3 & DOT 4 etc., but my understanding is that within those specs, not all are formulated equally (why would they be?). Any experience-based opinions on best quality brake fluid?

 

Like Antifreeze I bet there are no more 3 or 4 Manufactures who make Brake Fluid .

Just a whole bunch of private label brands.

In my Years I have never even heard any sales people pitching one brand of Brake Fluid over another just which brand was on special.

I just bought what was on the Shelf in the Gallon Container where I happened to be.

It all needs to be close enough to play nice together no one has a clue what is in the system before .

Has something new Come out within the last few years quite possible I look to learn new things all the time

 

I ordered some revenol 5.1 from Amazon (they also make the Toyota specified equivalent of our t case oil for a lot less $, which I have in the garage and will swap out soon). It has a much higher boiling point than dot 3 & 4. Curious to see if it has any noticeable improvements when the truck is loaded up. Quite likely overkill but not much more expensive.

 

Be Good to know How it works out

 

Assuming you have a 3rd gen, and Toyota still recommends DOT 3 for 3rd gens. Regardless, I used Preston DOT 3-4, it was on sale and I wanted 2 quarts to flush the brakes out. It’s DOT 3 that can take DOT4 temperatures. It may be just DOT 4 but my 2nd gen manual recommendation was for DOT3. Don’t go to DOT5 its different, silicon based I believe.

 

Pentosin Super DOT 4 has worked well for me

 

Yea dot 5 is incompatible with most abs systems and doesn’t mix with other grades. But 5.1 is compatible (meaning you don’t have to get every last bit of dot 4/5 out before swapping).

 

Just reporting back on this in case anyone’s interested. I flushed with Ravenol DOT 5.1 and brakes are definitely more responsive. That said, this is my first flush since I’ve had the truck, so maybe results are the same as they’d have been with DOT 3. The real test will be fade under load.

So fwiw, there you go.

 

Having had two bad experiences on other vehicles with generic brake fluids, I would only use OEM fluid as specified in the manual. It may cost more but can save big money in failures avoided. These abs systems are too complex, and costly to take chances. Toyota spends big bucks in R&D to determine and test what works best in their systems. Why experiment? Generally, if you have a pre- abs system, I'd use whatever dot number fluid was spec'd for it unless it calls for LMA or something else specifically.

 

Name brand DOT 3 at a minimum.

 

Like oil and other fluids get the cheapest that meets required specs. Brand doesn't matter

 

Coming down Old Priest grade outside of Yosemite in my 2nd gen 4Runner on 36s, my brakes were bellowing smoke. I was letting the engine take as much as it could but the brakes were almost nothing when I got to the bottom. Granted my taco’s brakes are bigger, but for the negligible increase in cost of a bottle of 5.1, I’d say that if this fluid made the difference in only those types of infrequent conditions, it’s worth it. I mean, I spent $15 bucks on a bottle of Ravenol 5.1 big enough to flush and fill my system. What’s top shelf DOT 3 at the parts store? $8?

 

It wont make a difference but if it makes you feel good

 

Why not?

 

A brake upgrade would be nice but we’re suddenly takking several hundred dollars and considerably more labor vs another $7 and a flush..,

 

DOT 5.1 is a non silicone, high temperature performance brake fluid that is ABS compatible. It is currently used on race cars which cannot use DOT 5. Personally have used it for over 15 years with no ill effects at all on a ABS equipped truck. It can withstand more heat from brake applications when towing and thus my reason for putting it to use.

 

Thanks for the feedback. This is what I was wanting to hear. Have you noticed any improvement in performance vs DOT 3 / 4?

 

Lots of ignorance and misinformation as usual.

The reason for changing brake fluid is it absorbs water. (Same reason you never store an opened container for anything beyond a few months at worst). Under high heat situations like heavy braking the water will boil and turn to gas which reduces the pressure in the line and your pedal fades and the vehicle speeds up. I have experienced brake fade / boiling on the racetrack. It is scary as hell.

The biggest performance increase is from changing the fluid to fresh without any moisture absorbed into it. That is more important than what you put in. Putting in something with a higher boiling point and then not changing it regularly is no better than the cheapest dollar store fluid changed every 12 months.

My racebike gets the cheap stuff that my local supplier has on the shelf every day of the week. I buy the smaller bottles because 4 bottles of fresh sealed fluid can stay on my shelf for years but one larger bottle (that I saved money on in bulk) has to be thrown out a few months after being opened. I then change my fluid between races and always have fresh high performance fluid and never have had an issue. The pricey stuff absorbs water just like the cheap stuff and in no time one is no better than the other.

Now one further point. Just because your hydraulic brake system is “sealed” don’t assume the fluid can’t pull in moisture. I have had brakes that didn’t leak but also couldn’t be bled no matter how many times we tried. Rebuilt the calipers and did the piston seals and they bled up in literally 30 seconds from a dry line. The seals would hold fluid but sucked air past them on the retract.

 

Amazing what a little Google comes up with.

https://en.m.wikipedia.org/wiki/Brake_fluid

Check the chart on dry and wet boiling points. That’s really the meat and potatoes of this discussion on performance. Everyone is worried about dry performance (fresh fluid with no water absorption). Once all have absorbed water the dry performance column is irrelevant and all are pretty much the same. Who wants to argue that DOT 3 is still inferior when regular changing will be ensure it performs to the same real world requirements and even exceeds the other’s performance if regular service is not adhered to?

 

I honestly cannot say that I felt any difference in brake pedal feel , it was changed over to DOT 5.1 for peace of mind. I use Motul 5.1 available on line or from Pegasus Racing.