Personally, I would do it every time you change brake pads / rotors at least. How hard do you drive? Any aggressive driving that might require hard braking? If you are hitting the canyons, then consider doing it more frequently. And if you do any track days, flush before the track day and after the track day.

I would take a look at the color of your fluid currently. If it looks dark or dirty, consider doing a fluid flush. Brake fluid can slowly accumulate water over time which boils a lot easier than brake fluid, so even if you don't drive hard, it is possible that you are getting a little air in the line from water boiling from brake heat.

Cost wise, I wouldn't know. I haven't paid a mechanic to work on any cars of mine for years. If you are at all handy with tools, try doing it yourself (if you feel comfortable about it). Dealers usually lump the cost of the fluid flush in with other services such as a brake job or general maintenance package. I would call your local mechanic or stealership and just ask around. Get multiple quotes to give you a better idea.

 

I don't think there is any real set time or mileage.
Water contamination is the biggest worry. Brake fluid is hygroscopic, that is its will draw moisture out of the air. How much it draws depends on conditions where you live. Hot and humid, change more frequently as there is more moisture in the air. Dry climate, maybe not so much. If there is any doubt whether the fluid is ok, just test it with something like this:
https://www.walmart.com/ip/Brake-Fl...l4=pla-1103062128822&wl12=169181238_10000001543&wl14=Brake Fluid Tester&veh=sem
If the light is green, its good. If its yellow, still good but probably time to change soon. Red and its time for fresh fluid.
Doesn't cost me any more than whatever a bottle of fluid is. I'm sure the dealer will charge you at least a couple hundred to do it.

 

I had no idea there were brake fluid testers out there! That thing probably just measures resistance across the prongs to determine how much water there is. Brilliant! Thanks for the heads-up!

 

I had no idea there were brake fluid testers out there! That thing probably just measures resistance across the prongs to determine how much water there is. Brilliant! Thanks for the heads-up!

Many chain service providers in the US do it as a courtesy when you have your oil/filter changed.

Changing the complete brake fluid with a car having ABS is not as simple as "OLD SCHOOL" brake system. So I would advise to carefully read up on the procedure in a FACTORY SERVICE MANUAL or get a freind that works in a shop that has ALL DATA print up the procedure.

I change my brake fluid in all my vehicles no matter the recommendations at least every 12mo. If I sport drive or race then that can be even more frequent. On my Motorcycles it is every race day or week end ride in the mountains. In the MINI R53 about the same as the bikes, the other rides it depends. Brakes are the most important safety equipment second only to seat belts and air bags.


Brake fluid is also another fluid that can be tested and analysed through Black Stone Labs.
https://www.blackstone-labs.com/


In the past before I started to follow my own advise I posted here the bottoms of my feet got real sore having to STOP a car that I did not service the brake system more frequently then prescribed.

 

Change mine every 2-3 years.
I provide the fluid.
Should only take 10 mins if using old method of pumping the foot pedal with 2 people. 5 mins if using a pump/gravity feed with one person.

 

The Mazda service schedule for Europe specifies replacing the brake fluid every 2 years or 24000 miles whichever comes first.

 

Once or twice/yr, I suck out the master cylinder fluid and put in new. Then about every 6 or 7 years, I get the system bled.

On an old Benz we kept for 25 years, it says to replace every year or ever other. One of the brake calipers would be found dragging at times. Replacing the fluid fixed that. I used to do it myself.

Ralph

 

I wrote my dealer's service manager and Mazda. Here is what they said.

Service Manager
"For North American cars they do not require a brake fluid flush, being the fluid is hydroscopic and in Canada and South America and Europe get flushed every 2 years same as most European vehicle’s , we still recommend the service for those reasons."

Mazda
"Mazda has no official recommendation on replacing brake fluid. Mazda recommends replacing the brake fluid as directed by a certified technician."

 

I wrote my dealer's service manager and Mazda. Here is what they said.

Service Manager
"For North American cars they do not require a brake fluid flush, being the fluid is hydroscopic and in Canada and South America and Europe get flushed every 2 years same as most European vehicle’s , we still recommend the service for those reasons."

Somebody needs to look up that word. It means something that uses an optical device to look under water.....:laughing001:
How is it that this guy thinks that the air in North America has no moisture content?
Hygroscopic is "the phenomenon of attracting and holding water molecules from the surrounding environment". So, as the DOT 3 or 4 fluid used by Mazda is hygroscopic, it does get contaminated by moisture. When it gets to 2 or 3 percent moisture content, its time to flush and replace. Thats where the test pen come in....:smile2:

 

Don't fix it if it ain't broke, if it's hard to brake or dirty the change it.

Else don't do anything

 

Easy to suck all the fluid out of the reservoir and then refill with fresh. It'll eventually diffuse to all the fluid. Do it a couple times/yr, and it'll very likely keep it from accumulating very much moisture.

Wonder why they don't put little silica gel pots on the air vent to the master cylinder. That would keep it from accumulating moisture. Just replace the silica probably about once/yr.

Ralph

 

sooooooooooo Ralph... you activate your ABS often do ya? :nerd: Perhaps those tempting rain wet and very large empty warehouse parking lots on weekends when no one is around and you can brake and slide all over without hitting anything or anyone. Otherwise that procedure will not recirculate fresh fluid from the reservoir in the most important safety part of a MAZDA brake system. :001_tt2 1:

 

If you flush the brake fluid every 3 years, the fluid down in the calipers will not get rusty in my experience. Just changing the fluid in the reservoir is a complete waste of time.

Dave

 

Agree, and my experience with this goes back to the mid-70s. I've neglected the flushing process on a few cars I've owned and ended up regretting it. It's cheap preventive maintenance to get it done every two to three years. I do find it incredible that Mazda doesn't prescribe this for the US. I have to think this was an administrative oversight with regard to what appears in the US maintenance chart and it's comical to see a Mazda technician (or anyone having experience with brake fluid) supporting it. If the entire brake fluid system was completely and forever air tight and never exposed to any humidity or temperature variations, I might even think about not changing it. But to let it go for say, 10 years is absolute folly. I've seen brake lines on vehicles rust from within and burst, calipers sticking, etc.... Last I checked, I think it costs around $100 to have the dealer flush and fill the brake system. No big deal for an every two to three year action.

 

Depends on if you have a sensitive left foot. With gen2 i found around 35,000km+ the pedal response wasnt as prestine.

 

I have been told to try to get the brake fluid changed every 2 years.

 

That's good advice depending on where you live. In dry climates, every 3 years should be fine. But there are simple brake fluid testers available to measure the amount of moisture that has been absorbed.

In reality, changing brake fluid is cheap and easy, so I lean towards 2 years.

 

It can also be checked with a multimeter, put one end into the fluid and the other onto the metal casing if voltage is over 0.3v it needs changing.

 

Wow, that's a cool way of checking! What would the voltage read if the fluid were just changed? 0.1V? 0V?

 

i call bullshit on that. He didn't even mention how close the prongs of the multimeter need to be to each other.

 

Are we going to dig up 7 month old threads now?

 

Old thread but seems the right place to ask.

I was looking in the service manual at the brake bleed procedure as I am changing the fluid in a week. It doesn't give an order as far as which wheel the bleed 1, 2, 3, 4. But it seems to describe doing the front first than the rear.

My question is about the rear. The manual describes depressing the piston to bleed the system. i have not seen this in other vehicles with integrated parking brakes. Why does Mazda recommend this? Also, if you do the rear after the front and open the system to depress the caliper air may get in?

Anyone have insight to the Mazda recommended bleeding procedure?

 

For any car (can't understand how a Mazda would be different), always start with the caliper FARTHEST away from the master cylinder, usually passenger side rear. Yes, have someone loosen the bleed screw on the caliper while you depress (AND HOLD) the pedal while they tighten the screw again....then let go (this will draw fluid from the master cylinder into the line). DO NOT ALLOW THE PEDAL TO COME UP IF THE PERSON HELPING YOU DID NOT TIGHTEN THE BLEED SCREW...talk loudly to each other and make sure you hear and understand each other during the process or you'll suck air into the system. Frequently check the level in the master cylinder and keep putting in fluid as it is pushed out of the calipers while doing this procedure.

 

I do the same. Bleed the fluid from the longest pipe run first, once it is cleared do the second longest etc. This is the traditional method , I've always been told it minimizes the chance of air/dirty fluid escaping the bleeding process.

As an aside, I had a Datsun 1600 (P510) as a teenager nearly 50 years ago- they were fast for the time and great & simple to modify.

 

As an aside, I had a Datsun 1600 (P510) as a teenager nearly 50 years ago- they were fast for the time and great & simple to modify.

My first car was fixed-up '72 510. Loved it. Wrecked it. Got a Datsun 1600 roadster after that - also called Fairlady before the Z car. Those had the SPL310 designation ('65) and the SPL311 designation for '66-'70. The 2000 roadster was SRL311 if I remember correctly.

Sold my roadster after kids came along. Looking back I'd like to sell the kids and keep the roadster. :shocked: Just kidding! Sort of.

 

Per the ASE, it is recommended that you change it every 2 years.

 

On most modern cars, every 2 years is overkill, just like 3K oil changes. When changing pads, bleed a few drops out of one of the calipers and check the color on a white piece of paper. If its clear, your in pretty good shape. If it's green or tinted, flush the system.

Attached is a pic of 15yr old brake fluid with 230K, notice the very dark green tint. The customer came in with the brakes overheating. The brake fluid had so much water content, it turned into gel in the cold weather, so that the brakes wouldn't release fully. I just replaced fluid and all is good. I have seen many cars go 5 year / 100K without causing issues.

 

Just to follow up. I used my Motive power bleeder and bled from closest to furthest. Didn't follow the what appears to be unnecessary steps for the rear.

Worked fine. Pedal is just slightly better.

 

Actually, you need to change your brake fluid when its contaminated, period, there is no set time schedule. Use a tester, change accordingly...

 

Late to the party, but all things aside, brake fluid should be translucent. The minimal change interval *regardless* of recommendations, is two (2) years for DOT 3. If it's looking dark, then it's overdue to be flushed. It's regular maintenance like any other, and doing so ensures proper performance of the brake system.

Not sure about DOT 4 and DOT 5.

 

isn't the correct procedure to use Forscan (or similar) to cycle the ABS pump whilst bleeding conventionally ?

I'd go with the test and replace method too

 

Lots of discussion about when you should properly change things and how, but what about the brake fluid itself?

We are supposed to use DOT 3 brake fluid in our cars, from what I understand. Any brands better than the OEM stuff?
CK

 

I interchange DOT 3 and 4, trying to get all DOT 4 because it is higher boiling.

Ralph

 

The rule of thumb is you can add DOT 4 to a system that uses DOT 3 but you should not add DOT 3 to a system that uses DOT 4.