Which Brake Fluid ? Prestone Valvoline or Castrol

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ATE Blue has been mentioned but I use it in my car and the blue coloring makes it really easy to see the transition. Their regular colored stuff is the same thing so you can swap back and forth.
 
All seems OK for ABS, but with the same pricing range, I would go with DOT 5.1 if I can find it on the shelves. At least it is certified on lower viscosity.
 
I like the Castrol GTLMA synthetic made in Germany, which advertises low moisture activity (LMA). However, it's hard to find these days. It's available at the ARCO/BP gas stations though.
 
Originally Posted By: Jss21382
You can run dot 4 in any vehicle that specifies dot 3, dot 5 is another story though.
Wellll..... There is a difference in the chemical composition of DOT3 and DOT4 fluids--the borate additive gives the DOT4 the higher wet boiling point, and----some elastomers in the brake system might not be compatible with this product. I had a master cylinder leak on my Tundra using DOT4, and I'm not sure it would have been OK with DOT3. The DOT4+ and DOT5.1 fluid are compatible with DOT4 and even higher wet boiling points, but also maybe not suitable for certain vehicles' brake system components.


By the way, ALL brake fluids are synthetic. There is nothing natural about polyglycol ether (nor DOT5 silicone brake fluid). Any non-synthetic brake fluids might be the hydraulic oil used in some tractor brakes, and that isn't in this discussion.
 
yay for reviving a 4-yo thread
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@Ken2, FMVSS116 *requires* brake fluid to be compatible with components used in brake systems.
 
Originally Posted By: wantin150
ATE Blue has been mentioned but I use it in my car and the blue coloring makes it really easy to see the transition. Their regular colored stuff is the same thing so you can swap back and forth.


I don't think any of us are going to have much success finding ATE Blue any longer. DOT made them recall it. Apparently, DOT3 and DOT4 specifically require brake fluid to be clear or golden color. Thus, the blue does not meet the standard. ATE is offering to buy back any ATE blue.
 
Originally Posted By: tommygunn
@Ken2, FMVSS116 *requires* brake fluid to be compatible with components used in brake systems.


S5.1.10 Compatibility.
(a) At low temperature. When brake fluid is tested according to S6.10.3(a), the test specimen shall show no sludging, sedimentation, or crystallization. In addition, fluids, except DOT 5 SBBF, shall show no stratification.
(b) At 60 °C. ( 140 °F. ) . When brake fluid is tested according to S6.10.3(b)—
(1) Sedimentation shall not exceed 0.05 percent by volume after centrifuging; and
(2) Fluids, except DOT 5 SBBF, shall show no stratification.


S5.1.12 Effects on (styrene-butadiene rubber wheel cylinder) cups. When brake cups are subjected to brake fluid in accordance with S6.12—
(a) The increase in the diameter of the base of the cups shall be not less than 0.15 mm. (0.006 inch) or more than 1.40 mm. (0.055 inch);
(b) The decrease in hardness of the cups shall be not more than 10 IRHD at 70 °C. (158 °F.) or more than 15 IRHD at 120 °C. (248 °F.), and there shall be no increase in hardness of the cups; and
(c) The cups shall show no disintegration as evidenced by stickiness, blisters, or sloughing.


S5.1.13 Stroking properties. When brake fluid is tested according to S6.13—
(a) Metal parts of the test system shall show no pitting or etching to an extent discernible without magnification;
(b) The change in diameter of any cylinder or piston shall not exceed 0.13 mm. (0.005 inch);
(c) The average decrease in hardness of seven of the eight cups tested (six wheel cylinder and one master cylinder primary) shall not exceed 15 IRHD. Not more than one of the seven cups shall have a decrease in hardness greater than 17 IRHD;
(d) None of the eight cups shall be in an unsatisfactory operating condition as evidenced by stickiness, scuffing, blisters, cracking, chipping, or other change in shape from its original appearance;
(e) None of the eight cups shall show an increase in base diameter greater than 0.90 mm (0.035 inch);
(f) The average lip diameter set of the eight cups shall not be greater than 65 percent.
---more---


By the way, FMVSS = Federal Motor Vehicle Safety Standard which includes all the U.S. regulations covering vehicle lighting, brakes, motorcycle helmets, and much, much more.
 
Originally Posted By: Ken2
. Wellll..... There is a difference in the chemical composition of DOT3 and DOT4 fluids--the borate additive gives the DOT4 the higher wet boiling point, and----some elastomers in the brake system might not be compatible with this product. I had a master cylinder leak on my Tundra using DOT4, and I'm not sure it would have been OK with DOT3. The DOT4+ and DOT5.1 fluid are compatible with DOT4 and even higher wet boiling points, but also maybe not suitable for certain vehicles' brake system components.



This is a very serious concern, I'm not sure why it is not more discussed.

My older Honda Accord from 1994 (well past the time when DOT4 was introduced) specifically states use DOT 3 brake fluid.

While my 1996 VW Golf GL says to use DOT4.

So the question is will using DOT 4 in that older Accord destroy the rubber or plastic components in the brake system????
 
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Originally Posted By: antiqueshell
Originally Posted By: Ken2
. Wellll..... There is a difference in the chemical composition of DOT3 and DOT4 fluids--the borate additive gives the DOT4 the higher wet boiling point, and----some elastomers in the brake system might not be compatible with this product. I had a master cylinder leak on my Tundra using DOT4, and I'm not sure it would have been OK with DOT3. The DOT4+ and DOT5.1 fluid are compatible with DOT4 and even higher wet boiling points, but also maybe not suitable for certain vehicles' brake system components.



This is a very serious concern, I'm not sure why it is not more discussed.

My older Honda Accord from 1994 (well past the time when DOT4 was introduced) specifically states use DOT 3 brake fluid.

While my 1996 VW Golf GL says to use DOT4.

So the question is will using DOT 4 in that older Accord destroy the rubber or plastic components in the brake system????

DOT 4 is a performance standard. There is nothing that wouldn't allow a fluid meeting all DOT 4 specs to be labeled DOT 3.

I drove a 1989 Acura Integra RS. The independent shop that serviced it a bunch of times always used Castol GT-LMA DOT 4. It had a pretty standard Honda gray brake fluid reservoir cap. Just check for pictures, and they always says "DOT 3 OR DOT 4" on them.

And although the OP probably isn't reading this - Wagner Severe Duty DOT 5.1.
 
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My favorite brake fluid: Castrol DOT 4 Synthetic Brake Fluid with unique "Low Moisture Activity" formulation. Wet boiling point: 329 F. Made in Germany. I got it at a local ARCO gas station for $4.49 + tax.

IMG_4946_cropped.jpg


IMG_4949_cropped.jpg


Not to be used in any car that demands any less than the highest possible brake performance.
smile.gif
 
In the last 20 something years, I haven't used any other Brake Fluids than Walmarts Tech2000/SuperTech & AAP/WearEver(on sale/2-4-1)
 
Originally Posted By: y_p_w
.... DOT 4 is a performance standard. There is nothing that wouldn't allow a fluid meeting all DOT 4 specs to be labeled DOT 3....

Completely agree with this statement. If I chose to, I'd have no reservations about using DOT4 where DOT3 was or is the spec. DOT4 has a higher dry/wet boiling point, which makes it an upgrade from DOT3.

Valvoline sells it's BF labeled as DOT 3&4 likely just at address any needless concerns regarding which to use.

http://www.valvoline.com/products/brands/valvoline/dot-3-4-brake-fluid/28
 
Regarding seal compatibility of Castrol (LMA) DOT 4 synthetic, I've had no issues with it whatsoever. I've used it for many years and several years ago I used it when I was rebuilding my master cylinder and it still runs as good as brand-new.

It seems to me that DOT 4 gives you an added degree of protection and peace of mind against DOT 3 and I wouldn't use DOT 3 just to save a few bucks. A DOT 4 fluid probably lasts a lot longer than a DOT 3 fluid as well.

Ongoing DOT 3 specification by car makers is likely because of a lack of worldwide availability of DOT 4, even though the former is an inferior brake fluid.
 
Originally Posted By: Gokhan
My favorite brake fluid: Castrol DOT 4 Synthetic Brake Fluid with unique "Low Moisture Activity" formulation. Wet boiling point: 329 F. Made in Germany. I got it at a local ARCO gas station for $4.49 + tax.

IMG_4946_cropped.jpg


IMG_4949_cropped.jpg


Not to be used in any car that demands any less than the highest possible brake performance.
smile.gif



AGREED, as far as "on the shelf" DOT 4s go (IF one can still find it on their fave store's shelf
wink.gif
).

I pay <$10.00 for a quart of this at my local indie store, one of the VERY few which still stock it on the shelf.
 
Originally Posted By: JustinC25
Originally Posted By: mechtech2
Justin - With brake fluid, anybody's is just fine. And this is coming from a lube and snake oil guy!

But your bleed method is relying on luck. You really need to open and shut the bleeder in concert with a helper pressing and releasing the brake pedal. Your method is only guaranteed to work with speed bleeders - an aftermarket replacement. Or use a vacuum like a Mity Vac. Super easy.


My method worked fine on my Camry, and my van already.
When I opened the bleader, I waited for some fluid to flow by gravity before I pumped. 1 pump was more than enough to fill the tubing, and I already had fluid in the catch bottle so it wouldn't suck any air back in. Then just keep pumping, and checking the master cylinder, until the fluid in the tubing became clear. It took about 20 pumps for the rear wheels, and 15 for the fronts.


How did you make sure you were not sucking air past the bleeder threads?
 
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