Every three years regardless of mileage as per the owners manual. Also helps keep a firm brake pedal no matter the age of vehicle.

I most recently replaced the fluid in my 1995 F150 when a left front brake line broke as o was approaching an intersection. Luckily I was still in my neighborhood driving slow and was able to steer in to a vacant lot to stop.

We replace ours every 3-5 years. I can’t tell much of a difference at 3 years but it’s noticeable at 5 years after it’s done.

This message has been edited. Last edited by: Sig Sauer Kraut,

Only when I had my Corvette. But that was easy as I had speed bleeders on the calipers. Also had a speed bleeder for the clutch.

I usually do it between 50-60k miles or about three years since that’s usually how many miles I accumulate.

So far for the last three cars I end up doing the rear brakes (pads and rotors) around 45k-50k and the fronts (pads and rotors) usually need replacing around 55k. That’s when I will flush the brake fluid.

Aren't you supposed to change blinker fluid at the same time?

quote:

Originally posted by V-Tail:
Aren't you supposed to change blinker fluid at the same time?

I think that requirement changed in KY secondary to lack of use.

quote:

Originally posted by V-Tail:
Aren't you supposed to change blinker fluid at the same time?

Not sure if that is meant to be a joke or a joke on people that do change the fluid. When my wife and children are depending on me to make sure their car is as safe as possible, I take no chances. Not changing brake fluid won't lead to an accident for sure but it certainly can. Why take the chance. Changing fluids, even early, is simple insurance.

Now if it was a joke about blinker fluid and such, carry on

Thanks for the replies, fellas. I see it's done more often that I thought. I guess this is a good reminder then for all of us.

I did it when I changed calipers maybe 40k ago, And again when a brake line ruptured.

If you use speed bleeders and use a different color fluid like ATE blue, you can just pump each caliper until the fluid changes color while topping off the reservoir.

Simply put, "Yes!"

Once a year; complete replacement. Having any gas or water in the line(s) is horrible when at speed, you need to slow and the peddle goes to the floor. Ain’t nobody gots time fo’ dat.

I try to get it done about every 2 to 3 years. God Bless

When it looks more like Guinness than Coors light.

quote:

Originally posted by cruiser68:
I swap brake fluid every two years regardless of mileage. Brake fluid absorbs water over time whether you are driving the car or not. When moisture gets into the lines it does two things. First it starts rust inside the brake lines. Second, when compressed the water boils and puts air into your system. If you have a power bleeder it makes the process pretty simple.

I have done brakes on friends cars that never changed the fluid. On some the fluid was so dark and dirty it actually damaged a caliper.

And when the water attacks the brake lines the resulting oxidation consumes the anti-corrosion inhibitors faster than otherwise. Also Dot 3,4, and 5.1 are interchangeable and can be mixed if you're not willing to drain the entire circut. But Dot 5 is not mixable with any of the other three, because it is silocon based, which doesn't absorb water. In fact adding Dot 5.1 to any of the others would create braking problems because the two products are not phsycially or chemically miscible, therefore the specific gravity of the different fluids in the lines would vary with location in the line. I don't know anything about fluid physics byt my understanding is that doing so would serious braking problems and would be completely unsafe. Next time I'm messing with brake fluids in the cars I maintain I'll be switching them all out with Dot 5.1 depending on price. So far I have not found any Dot 5.1 that is priced reasonably, in which case I'd upgrade to Dot 4. As far as I know all three share the same basic chemistry, but in general with some exceptions the boiling point increases from 3 to 4 to 5.1.

I changed fluid on a truck I owned at a major brake job. I think it is a good idea.

For the record, in roughly a bazillion miles with each car I've owned going 140-180K before sale, I've never ever replaced a caliper.

Maybe there's a reason some folks can say never change fluid until caliper is jacked up.......

I put new roters on & a couple of calipers. Bled and siphoned out reservoir put new in.
That's all. 200k miles.

You have to do it on Motorcycles.

Not sure if cars have a stainless steel master cylinder or an aluminum one, that would make a huge difference.
Aluminum has a chemical reaction with brake fluid and that fluid must be changed at certain intervals.

Most motorcycles have aluminum if not all. I had motorcycles all my life and was not aware of that until about 12 years ago. The brake fluid will turn orange and is pretty useless then.
I always wondered if synthetic brake fluid would not have that chemical reaction???

Flush at every pad change. Regardless of if I do it or have it done. The shop that does the service that I don't want to do, or don't have time to do, used to include the flush at no extra charge, but only if requested... then they started charging a few extra bucks for the extra fluid, now they charge an extra 30 bucks. Money well spent IMO. Other wise they just do the minimun necessary bleeding.

FYI it is not nearly as good as an actual flush, but the old
"turkey baster" fluid change can very easily be done for anyone not inclined to do an actual flush/change.
Just suck out all the fluid you can from the master cylinder and replace with new... doing this 2 or three times at monthly intervals will go a long way toward refreshing the fluid. Easy, cheap and better than nothing!

I always eyeball the level and appearance of the brake fluid at every oil change. If it doesn't look 100% perfect it gets sucked out and replaced.