Change Brake Fluid at 30,000 Miles?

Don't tell your wife but don't reuse the turkey baster either...
I save the "pump" from a shampoo bottle and rinse it well. Then just pump the fluid out into a jar. Seems less messy than the baster, it always drips. And no food contamination.
 
The UK service schedule states every 2 years/24k IF THE UNITS HAS BEEN SUBMERGED IN WATER. So no change recommendation for average driver based on this.
 
The UK service schedule states every 2 years/24k IF THE UNITS HAS BEEN SUBMERGED IN WATER. So no change recommendation for average driver based on this.

That is for the rear diff oil. Water can get in through the breather.

Brake fluid must be done every 2 years.
 
Interesting how Mazda recommends replacing brake fluid @24 months or 40k km in Mexico, but has no such recommendation for the US.
Yeah, very strange. My 1998 Honda CR-V has 36-month/45,000-mile brake fluid replacement maintenance interval. But I was too lazy to change it now it's been 19 years and 177,099 miles and it still uses brake fluid from factory! Hopefully the ABS or any calipers and cylinders won't fail any time soon. BTW, rear drum brake shoes are still original too! :)

For some reason I always thought you don't mix DOT4 brake fluid with our DOT3's.
 
Yeah, very strange. My 1998 Honda CR-V has 36-month/45,000-mile brake fluid replacement maintenance interval. But I was too lazy to change it now it's been 19 years and 177,099 miles and it still uses brake fluid from factory! Hopefully the ABS or any calipers and cylinders won't fail any time soon..............

Wow , Yrwei52, that must be some kind of record LOL 19 years ? original brake fluid .....

maybe check with a cheapo tester ? just to be safe......

https://www.amazon.com/dp/ (commissions earned)
 
Yeah, very strange. My 1998 Honda CR-V has 36-month/45,000-mile brake fluid replacement maintenance interval. But I was too lazy to change it now it's been 19 years and 177,099 miles and it still uses brake fluid from factory! Hopefully the ABS or any calipers and cylinders won't fail any time soon. BTW, rear drum brake shoes are still original too! :)

For some reason I always thought you don't mix DOT4 brake fluid with our DOT3's.

And hopefully you wont have any long downhill runs when carrying a decent load, where you need to be on the brakes for long enough to get them really hot!

I also had understood that mixing dot 3 and 4 isnt a good idea. Most master cylinder caps here are marked dot 3 or 4 so you know which one to use.

But, I recently did a fluid chnage on my boat trailer brakes, and was shown some castrol fluid that was both dot 3 and 4 compatible.

Btw the trailer's brake fluid was looking very discoloured. Is got one of those 1 person kits and bled them thru, until I got nice clean fluid coming out of the bleeder. Took about a pint all up to thoroughly flush both sides (single axle trailer)
 
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And hopefully you wont have any long downhill runs when carrying a decent load, where you need to be on the brakes for long enough to get them really hot!

I also had understood that mixing dot 3 and 4 isnt a good idea. Most master cylinder caps here are marked dot 3 or 4 so you know which one to use.

But, I recently did a fluid chnage on my boat trailer brakes, and was shown some castrol fluid that was both dot 3 and 4 compatible.

Btw the trailer's brake fluid was looking very discoloured. Is got one of those 1 person kits and bled them thru, until I got nice clean fluid coming out of the bleeder. Took about a pint all up to thoroughly flush both sides (single axle trailer)
3 & 4 are compatible, you can't mix them with 5 because 5 is silicone based.
 
I've used this stuff for years with good results.

588245.jpg
 
Yeah, very strange. My 1998 Honda CR-V has 36-month/45,000-mile brake fluid replacement maintenance interval. But I was too lazy to change it now it's been 19 years and 177,099 miles and it still uses brake fluid from factory! Hopefully the ABS or any calipers and cylinders won't fail any time soon. BTW, rear drum brake shoes are still original too! :)

For some reason I always thought you don't mix DOT4 brake fluid with our DOT3's.

Good luck with this.
 
Wow , Yrwei52, that must be some kind of record LOL 19 years ? original brake fluid .....

maybe check with a cheapo tester ? just to be safe......

https://www.amazon.com/dp/ (commissions earned)
I'm truely surprised that the brake fluid and rear drum shoes can last that long without any issues on my CR-V. Like some retired friends who refuses to do annual physical checkup always said - what's good for to find something wrong at this stage? If anything major go wrong, I'll sell it cheap and pass the problem to him. I do plan to do brake fluid flush next time replacing front pads. Part of reason I didn't do brake fluid change is because I hate to deal with paint-eating brake fluid. BTW, all 4 struts/shock absorbers are original too but the front pair do need replacement right now.

And I do believe brake fluid requires periodical replacement based on manufacture maintenance schedule, or 2~3 years if there's no schedule like our CX-5. I'm just too lazy to do it. :)
 
I'm truely surprised that the brake fluid and rear drum shoes can last that long without any issues on my CR-V. Like some retired friends who refuses to do annual physical checkup always said - what's good for to find something wrong at this stage? If anything major go wrong, I'll sell it cheap and pass the problem to him. I do plan to do brake fluid flush next time replacing front pads. Part of reason I didn't do brake fluid change is because I hate to deal with paint-eating brake fluid. BTW, all 4 struts/shock absorbers are original too but the front pair do need replacement right now.

And I do believe brake fluid requires periodical replacement based on manufacture maintenance schedule, or 2~3 years if there's no schedule like our CX-5. I'm just too lazy to do it. :)

"If anything major go wrong, I'll sell it cheap and pass the problem to him."

The problem is that if anything major goes wrong in this scenario you may find out what happens when you have zero brakes when you need them the most. This sounds like an accident waiting to happen. Oh well...
 
"If anything major go wrong, I'll sell it cheap and pass the problem to him."

The problem is that if anything major goes wrong in this scenario you may find out what happens when you have zero brakes when you need them the most. This sounds like an accident waiting to happen. Oh well...
Yeah, thanks for the warning and believe me I truely aware the danger of having 19-year-old brake fluid! When I said anything major I meant the broken ABS pump、leaking calipers or cylinders and the buyer would have to spend extra to fix it. Our Honda CR-V now has very limited use and serves as a backup vehicle only. I frequently tell friends and family to change the brake fluid periodically as many people never change the brake fluid even when they have brake job and the shop would never tell them to change it either! I do believe that's the problem here in the US that it's a common practice the brake shops never include brake fluid change as a part of brake job, and they're not interested to educate customers to change the brake fluid either!
 
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Going through a similar 'changing the brake fluid' conversation on my motorcycle forum. It seems that some of the guys haven't been changing the fluid in a timely manor and now have developed issues with their ABS pumps. A couple of them completely lost the rear brake because of corrosion in the system. The pump can't be repaired and must be replaced. Not cheap.

This is what can happen after the fluid absorbs moisture.
 
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Going through a similar 'changing the brake fluid' conversation on my motorcycle forum. It seems that some of the guys haven't been changing the fluid in a timely manor and now have developed issues with their ABS pumps. A couple of them completely lost the rear brake because of corrosion in the system. The pump can't be repaired and must be replaced. Not cheap.

This is what can happen after the fluid absorbs moisture.

I do not think that most people understand that the fluid is DESIGNED to absorb moisture. And such is the reason for a 2-4yr replacement interval, higher in more humid and tropical areas.

Once the brake fluid has absorbed as much moisture as it can hold, the excess moisture now settles out to the lowest points... Lowest points often include ABS pumps, Wheel Cylinders, brake calipers, etc. Now that these parts are filled with water, instead of brake fluid, rust and corrosion accelerates, or even failure from low temp freezing can now occur.

IMAG1096.jpg
 
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I do not think that most people understand that the fluid is DESIGNED to absorb moisture. And such is the reason for a 2-4yr replacement interval, higher in more humid and tropical areas.

Once the brake fluid has absorbed as much moisture as it can hold, the excess moisture now settles out to the lowest points... Lowest points often include ABS pumps, Wheel Cylinders, brake calipers, etc. Now that these parts are filled with water, instead of brake fluid, rust and corrosion accelerates, or even failure from low temp freezing can now occur.

IMAG1096.jpg
Now you can add what a 19-year-old Honda brake fluid looks like when I have a chance to flush it. But by looking through the reservoir of my CR-V it looks much better than 6~7-year brake fluid in the picture! I did have a first-hand experience where the water, which is heavier than brake fluid, settled at brake cylinders and corroded the cylinder wall! Yeah brake fluid requires periodical change but I wonder why Mazda doesn't put that into factory recommended maintenance schedule like Honda or others does?
 
Now you can add what a 19-year-old Honda brake fluid looks like when I have a chance to flush it. But by looking through the reservoir of my CR-V it looks much better than 6~7-year brake fluid in the picture! I did have a first-hand experience where the water, which is heavier than brake fluid, settled at brake cylinders and corroded the cylinder wall! Yeah brake fluid requires periodical change but I wonder why Mazda doesn't put that into factory recommended maintenance schedule like Honda or others does?
Perhaps because that would add additional cost to the all important "COST TO OWN" figures in the JD or Consumer Reports...
 
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