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Cleaning brake fluid (general tips)

Standard automotive brake fluid (DOT 3,4 and 5.1) are made from polyethylene glycol (PEG). PEG is soluble in water, methanol, ethanol, acetonitrile, benzene, and dichloromethane, and is insoluble in ...
Fred Wilson's user avatar
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9 votes
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What to do if you don't know if you have DOT 3 or DOT in your brake lines?

Dot 3 and Dot 4 are mixable, you can use whatever you want. Just do not put Dot 5 into it, thats a whole different thing and not mixable with Dot 3 or Dot 4.
Martin's user avatar
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8 votes
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Brake fade and spongy brakes at high speeds

Based on what you have posted, changing the brake fluid is not going to solve the problem. It's just going to provide a clean new fluid to boil when your brakes stick. If I read what you said ...
cdunn's user avatar
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8 votes
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Did I toast my caliper?

Any sort of brake fluid leak is a serious issue which needs to be fixed for several reasons. Any fluid leak means that air is also getting into the system which will accumulate and degrade braking ...
Chris Johns's user avatar
  • 1,586
8 votes

Is it sufficient to cycle out brake fluid as opposed to "replacing" or "flushing" it?

There's one slight problem with your theory. The fluid which goes out to the brake cylinders/calipers stays out there. It will never come back to the master cylinder. You have to do something to ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
8 votes
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Brake fluid heat

Short answer: It gets REALLY hot - like, way over 100C (decimal). And, as @SolarMike's answer states, the water that the fluid absorbs from the atmosphere likes to vaporize under those conditions. ...
3Dave's user avatar
  • 3,149
6 votes

Brakes don't work

If your brake pedal went to the floor it means that there was not enough hydraulic pressure to apply the brake. If they were working fine before and never felt squishy then your master cylinder has ...
rviertel's user avatar
  • 1,169
6 votes

Can I put DOT 4 brake fluid into DOT 3 brake?

You can absolutely use DOT4 in place of DOT3 brake fluid. The only thing you'll need to do is completely purge the system of the old DOT3 fluid to take advantage of the DOT4 features (higher boiling ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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Brake Fluid Bleeding Procedure

The ONLY way I've ever seen/heard/done to manually bleed the brakes is exactly like what the workshop manual is stating. You need to do it in the order presented or you'll be defeating your purpose. ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
6 votes
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How does the brake fluid return to reservoir in Disc Brakes after brake pedal is released?

In the caliper, the seal is designed so when you press the brake pedal and fluid enters, the seal twists sideways. When you release the brake pedal, the force of the seal pushes the piston and thus ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
5 votes
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Changing fluids (power steering and rear differential): when and why

When buying a used car it's usually a good idea to change all fluids, just so you know exactly when they were changed, and can start your own fresh service history. This may be part of the reason why ...
MooseLucifer's user avatar
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5 votes
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Motorcycle front brake lever too close to grip

It seems as though the plunger in the master cylinder isn't retracting after use Occasionally when motorcycles are stored you can run into this problem. Older brake fluid along with a bit of ...
DucatiKiller's user avatar
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5 votes

Is failing to change brake fluid a life safety issue?

YES. A big Y-E-S. It's a huge safety issue. See, braking fluid absorbs(even attracts) water over time, not so much over usage, if at all. Brake fluid gets really hot, even more under sustained braking ...
Bart's user avatar
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5 votes
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Brake caliper leak while pushing piston back

If your caliper has any brake fluid coming out of it, it's time to rebuild/replace the caliper. There should be absolutely no fluid loss anywhere in your braking system. If it is leaking at the ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes

Mixing DOT 4 with DOT 4 synthetic

DOT 3, 4 AND 5.1 can be mixed. They are compatible. None of them are compatible with DOT 5 that's silicone-based. I just bought some Motul DOT 5.1 and it says on the front label: "NON-SILICONE base ...
Houckster's user avatar
4 votes

Brake pedal soft after changing pads

A number of things could have happened: You let air into the system, either by pushing the piston out too far or by un-doing the bleed nipple. The system has developed a leak. You could have either ...
Newbie Noob's user avatar
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4 votes

When should brake fluid be changed in a Honda 2016 CRV?

Most cars have brake fluid changes every 2 years. It may be occasionally the case that car manufacturers experiment with longer intervals, finding them to be unsuitable and reverting back to the ...
juhist's user avatar
  • 14.6k
4 votes

Brake fluid heat

If there is a small amount of water in the brake fluid in the caliper and the brakes are used severely for an extended period the heating can cause the water to change to vapour. The issue is that ...
Solar Mike's user avatar
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4 votes
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99 Honda Odyssey had brake fluid flushed 4700 miles (27 months) ago. Does it need to be replaced again?

Brake fluid replacement is not determined by the amount miles on the vehicle, but by the amount of time. That's because it is hygroscopic, which means it absorbs water. It does this through the rubber ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
4 votes
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Why don't car brake systems generally use mineral oil as brake fluid?

The Bosch Automotive Handbook confirms that mineral-oil-based fluids are not hygroscopic: Mineral-oil fluids (ISO 7308) The great advantage of mineral-oil-based fluids is the fact that they are not ...
Zaid's user avatar
  • 39.2k
3 votes

Does brake fluid require topping-up as brake pads wear out?

Er, not so much. I'm assuming we're talking Motorcycle here, right? What if there is a slight leak in the brake lines somewhere? You'd be losing fluid and that would NOT be a good indicator of ...
zipzit's user avatar
  • 6,559
3 votes
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Specifics about changing a brake caliper on 2000 Toyota Camry

What hardware if any should be replaced every time the brake line comes off the caliper? I know there's a brass washer for the banjo bolt, but what is the criteria for replacing it? New/re-furbished ...
race fever's user avatar
  • 3,353
3 votes

Mixing DOT 4 with DOT 4 synthetic

Manufacturers have been labeling their DOT3 and DOT4 products as "synthetic" as many consumers associate this with higher performance or quality similar to motor oil. But ALL brake fluids can be ...
masospaghetti's user avatar
3 votes

What's a reasonable time for doing a one person brake bleed?

It can definitely be done faster, but that's a matter of experience. A vacuum cannister doesn't help me much, i always use this constuction and it has worked perfectly for me: It's the most ...
Bart's user avatar
  • 2,954
3 votes
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Is it ok to mix different clutch fluid color?

EDIT EDIT of my not being able to read: From the 96 Civic owners manual: "use Genuine Honda Brake Fluid or an equivalent from a sealed container that is marked DOT3 or DOT4 only. Brake fluid ...
Zshoulders's user avatar
  • 1,646
3 votes

Brake fluid what does it do if on ABS type plastic?

DOT3 should not affect ABS plastic. It is only detrimental to natural rubber and paint. It also absorbs water, which may cause rust/corrosion in steel brake lines. Other than that, you shouldn't have ...
Pᴀᴜʟsᴛᴇʀ2's user avatar
3 votes

When should brake fluid be changed in a Honda 2016 CRV?

Specifically (meaning as applies to Honda vehicles): Your engine oil needs to be in spec which is defined by Honda, you can deviate at your own risk. Oils may be incompatible with gaskets, etc. Most ...
finleyarcher's user avatar
3 votes

Do cars have a specific brake and power steering fluid or are they universal?

Vehicle manufacturers have a specification for all of their fluids and it should be in the owners manual. Many vehicles do share similar specifications for power steering and brake fluid, but it is ...
Milison's user avatar
  • 634
3 votes

Do I need to bleed the brakes or overhaul?

Some vehicles have much more sensitive brakes than others, so what you're describing may be totally normal. But, you should err on the side of caution and do the following if you think the brakes are ...
jwh20's user avatar
  • 12.1k
2 votes

Spongy brakes after brake pad swap - moisture or bubbles?

I have a older Cherokee that some how pulls in air when the caliper pistons are pushed in for a pad replacement. It does not make sense but I always have to bleed them after a pad replacement. I have ...
theKbStockpiler's user avatar

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