Only DOT 3 on O Reilly's shelf is Synthetic DOT 3? And how good would it be mixing it with the normal old stuff, and what effects on the seals in all the cylinders in the system? Can't be good for the old ABS system?
Did they get rid of normal DOT3 ?
- Thread starter Exhaustgases
- Start date
If the system is made for DOT3 [ DOT3 on the cap] I can't see how adding a fluid that meets that spec can be the wrong thing to do.
Yep, brake fluid is synthesized. It is basically polyethylene glycol. It is hygroscopic but does not swell rubber. In higher molecular weights, it is a solid and is sold as Carbowax.
There is no such thing as natural brake fluid and never has been!
There is no such thing as natural brake fluid and never has been!
Some old European vehicles used a mineral oil brake fluid. Tractors and industrial equipment too. Not even slightly compatable with the normal DOT stuff in wide use today.
Wet brake tractors and forklifts use mineral oil, commonly 32 weight.
I meant standard dot3, if its not different some how why do they even add the word synthetic?
5K lb Hyster f lift says DOT 3 on its cap? I agree though it should just be hyd fluid.
5K lb Hyster f lift says DOT 3 on its cap? I agree though it should just be hyd fluid.
If something requires DOT3 any DOT3 will work. The formulation of DOT3 is inherently synthetic. They just put Synthetic on there because it sounds cool.
Why would you be mixing brake fluid? A correctly functioning (i.e. non-leaking system) simply needs a flush and fluid replacement every 24 months or so.
Not totally true. It is normal to add small amounts as the brake lining material wears and gets thinner.
No, that's not normal. That's just silly. The reason there is a reservoir of fluid is so it doesn't need replenishment between pad changes.
Monitoring brake fluid level drop as pads wear is a easy quick pad wear check while your under the hood checking the oil.
Don't top it off, that's why its called a reservoir. And it defeats the purpose of the brake light low fluid warning.
Don't top it off, that's why its called a reservoir. And it defeats the purpose of the brake light low fluid warning.
Standard DOT3 is a synthetic fluid. Just because they add the word synthetic doesn't change the fact that all DOT3 fluids were synthetic to begin with.
I'm not talking about large amounts over a short period of time by any means. I'm talking minuscule amounts over a several year period. I maintain my vehicles better than most (probably better than you) and prefer to maintain levels at the full mark. If you wish to just keep it between the max and min marks, then good for you, topping off is not needed.
What’s the serial number I can look it up.
DOT fluid is a mix of glycol ethers, polyethylene glycol and (di)ethylene glycol with corrosion inhibitors, water scavengers and other additives. When you start getting into Japanese formulations as well as Euro DOT4/5.1, borate esters are added to increase wet boiling point.
There is HSMO - used in older Rolls-Royce/Bentleys and currently by Shimano and Magura.
There is HSMO - used in older Rolls-Royce/Bentleys and currently by Shimano and Magura.
So then it is and was just nonsense for the outfits marketing DOT3 to put the word "SYNTHETIC" on the bottle if it was always that. All my life I never saw that on a container of DOT3, I personally thought it was some new and fancy thing they were doing now.
Just looked at maybe 3 year old NAPA DOT3 fluid jug no mention of synthetic on it.
Nothing on these Honda bottles mentions synthetic.
https://www.collegehillshonda.com/product/08798-9008.html
Sorry to a person like me and likely others that are into details, it just didn't and does not make sense, to add that to the label if it is a nothing burger.
Sorry not all of us are Brake fluid chemists. I've just always hated the stuff.
Just looked at maybe 3 year old NAPA DOT3 fluid jug no mention of synthetic on it.
Nothing on these Honda bottles mentions synthetic.
https://www.collegehillshonda.com/product/08798-9008.html
Sorry to a person like me and likely others that are into details, it just didn't and does not make sense, to add that to the label if it is a nothing burger.
Sorry not all of us are Brake fluid chemists. I've just always hated the stuff.
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Well us non internet mechanics of the 1960's, would go Hmmm sometimes 6 plus years or more, and never change the brake fluid, and only do so when it leaked some place, like a wheel cylinder. And then only enough to fill up that replacement wheel cylinder. Yeah the good old days, especially for us poor highschool kids, with only pennys to buy parts with.
slo town
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It may not need replenishment if the level stays above the minimum, but the level will most certainly drop with pad wear.
Scott
Then why are dealers and parts places selling little tiny bottles of brake fluid? Please with all the wisdom, explain that?
Only shops are required to change fluid or lie about it between brake frictions replacements.
I've always gone untold years and not changed brake fluid. If it wasn't for dealing with a booster issue on my one car, it would have 70 plus some k miles and 25 years on the original brake fluid, and all is good, go figure. That was about 12 years ago, but then the front pads lasted and still had a bit of meat at 70K so?