How often to Change Brake Fluid?

[skyship]

Originally Posted By: Realtech214
2003 silverado 80000 Miles. how often to change brake fluid? I have never needed to add any fluid so I know there are no leaks


2 years for normal use, but every year if you have a serious big right boot. One of the main causes of caliper and even rare master cylinder failure is bad brake fluid.
It should be in the engine manual and might be 3 or 4 years if you use something very expensive.

 

[Sunnyinhollister]

I recently picked up a 1998 Jeep Wrangler and just got around to changing the brake fluid on Friday. Out of the 4 bleeder screws, one worked normally, two were blocked by rust at the wheel cylinder/caliper, and on the last one nothing was coming out until I completely removed the bleeder screw and poked an allen wrench into the wheel cylinder to make a path through the crud. There was a fair amount of sediment and flakes in the bottom of the bleeder container once I was done.

I think two years is a little excessive even though many manufacturers recommend it, but I would not go more than 5 years.

 

[GMBoy]

Originally Posted By: mechanicx
GM and Ford and basically Chrysler and the Domestics don't suggest a brake fluid change interval. GM uses DOT 3 which boiling point wet doesn't drop as much as DOT 4 and their particularly brake fluid is claimed to be longer life, along with EPDM lined hoses. GM instructs to not open the master cylinder cap and to not top up the brake fluid as the pads wear.

That said with ABS being so common, it wouldn't be a horrible idea to flush out the brake fluid after 4-5 years or when the pads are changed. It'd probably be best to use the Delco supreme II though rather than the common Prestone or Valvoline Dot 3,4. Really you don't need to bother with it.

I would add that I personally think that if you want to help extended the ABS modules life properly changing the brake fluid every 2-3 years even on Domestics is probably a good idea.



Absolute truth. I will add that the Delco Supreme brake fluid, which is factory fill on GM vehicles, has a special additive that allows it to work so well for so long. That is why GM hasn't recommended flushes. I, personally, do 2-3 yr flushes because a bottle of brake fluid and 30 minutes time is cheaper than a new ABS module.

 

[electrolover]

I like to flush it out when I do the brakes.

 

[skyship]

Originally Posted By: mechtech2
Originally Posted By: mikered30
Every two years is the recommendation to remove the water build up.


Gm says 7 years.
I never heard of 2 years from a mfr..
And where is this water coming from? It is a sealed system.


Tiny traces of water get past the calipers and into the brake fluid. If you use good fluid then just change it when the brake pads are changed. Calipers should last nearly 20 years but if you don't change the fluid they only last past the warranty, probably 10 years, but it depends on quality and environment. Same game with coolant, a radiator last longer if you change the coolant every few years, but it won't fail before the warranty expires so they probably won't say change it.

 

[SteveSRT8]

Originally Posted By: GMBoy
Originally Posted By: mechanicx
GM and Ford and basically Chrysler and the Domestics don't suggest a brake fluid change interval. GM uses DOT 3 which boiling point wet doesn't drop as much as DOT 4 and their particularly brake fluid is claimed to be longer life, along with EPDM lined hoses. GM instructs to not open the master cylinder cap and to not top up the brake fluid as the pads wear.

That said with ABS being so common, it wouldn't be a horrible idea to flush out the brake fluid after 4-5 years or when the pads are changed. It'd probably be best to use the Delco supreme II though rather than the common Prestone or Valvoline Dot 3,4. Really you don't need to bother with it.

I would add that I personally think that if you want to help extended the ABS modules life properly changing the brake fluid every 2-3 years even on Domestics is probably a good idea.



Absolute truth. I will add that the Delco Supreme brake fluid, which is factory fill on GM vehicles, has a special additive that allows it to work so well for so long. That is why GM hasn't recommended flushes. I, personally, do 2-3 yr flushes because a bottle of brake fluid and 30 minutes time is cheaper than a new ABS module.



Since we used to consult with a G team engineer who worked with our authorized factory upfitter we heard about this feature many moons ago. Another example of GM quality that gets little credit.

My oldest van still has original equipment calipers on it after 400k miles with one fluid flush. We ALWAYS buy genuine GM fluid as well.

 

[AITG]

As far as the sealed system goes, there has to be air admitted to the system. As the lining wears the pistons hold more fluid because they are extended. Some air has to be admitted or the system would be in a partial vacuum. The rubber cap on the master cylinder cover is designed to extend to take up the void but there has to be some air behind (above) it.

More importantly, replacing fluid exercises the bleeder screws. If you wait 10 years to move them, good luck.

 

[mattd]

every 2 years.

 

[mikered30]

I believe Lexus is every 30,000 miles. I don't think I ever saw one for Toyota though.

 

[lars11]

My grand cherokee says 48 mo or 60k. Ordinary dot3, dot4 or dot5.1 fluid definitely absorbs water from the air and should be changed regularly for two reasons:
1. It lowers the boiling point of the fluid causing brakes to stop functioning when braking heavily, like racing or going downhill/towing.
2. Corrodes brake lines and components from the inside.
I had to replace the steel lines on my 95 BMW because of this kind of ignorance (from the shop

). Not fun or well spent cash.

If you have a car with speciality components or like dot5 silicon based fluid, other recommendations may apply.

 

[shell_user]

I did my brake fluid change out at 87k when I did rear drum brakes, new wheel cylinders and all hardware along with parking brake cables. Just did it 2 weekends ago, as I did front brake pads, rotors. Mileage was 142k now at 143,009

adam

 

[Trav]

Originally Posted By: Papa Bear
Nothing in my 2007 Chev Uplander manual about changing brake fluid.

How can moisture get into the fluid if there is no leak?


Most brake fluids are hygroscopic. DOT 5 is not.