Brake fluid flush interval?
- Thread starter ron in sc
- Start date
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homeyclaus
New member
2 years is standard on just about every vehicle. Nobody does that. On the other hand, the 5th gens are self-bleeding from the ABS controller on down, so changing it is pretty easy.
Just make super, duper sure you don't run your master cylinder low. On many vehicles it's just a PITA - on the late model ABS systems you're going to go looking for a TechStream to make it happy again.
Just make super, duper sure you don't run your master cylinder low. On many vehicles it's just a PITA - on the late model ABS systems you're going to go looking for a TechStream to make it happy again.
1engineer
Moderator
I am in the camp of not changing or flushing brake fluid unless the system has been broken into due to a bad component or hose. You can and will introduce more contaminants into the closed system when you do the flush than what was in there before the flush. Same with transmissions. Of course some here will disagree and that's fine. I do have a little experience in this area though.
ron in sc
New member
I'm going to have to respectfully disagree with you on this one. I have always flushed fluid at 2 years max. on Mercedes vehicles and yearly on all Porsche vehicles.
I use motive pressure bleeder and have four collection containers that allow old fluid to exit and no fluid to get back into caliper.
My shop is pretty clean at least prior to starting a project so contamination has to date never been a problem.
I've been treating my vehicles like this for a long time and these vehicle have never had a brake or brake fluid problem. Some of the older cars are 22, 16,14, years old.
Some of these vehicles are driven very hard.
Whiplash Willy
New member
Are you not planning on changing your WS-ATF after 100k then?
mikebontoft
New member
mine is now...wow. 20 years old. It may have had a flush before but the moisture content is only at 1%. as soon as you get to 2% it's time to flush it.
1engineer
Moderator
That's why I put the disclaimer in there. Maybe I should clarify somewhat: If it's just a normal passenger vehicle that is not off road too much then I stand by my assertion. If it is off road a lot or is driven at (or like at) a track or if you tow a lot then by all means change it periodically, with the period depending on how hard it is driven and used. If it is a track car then change it often!
Brake fluid does not "wear out" for a long time, if ever. The big problem is moisture, which eventually will cause corrosion in the system. With the advent of the clear plastic reservoir you don't have to take the cap off to check fluid levels so the system will stay sealed and no moisture is introduced.
Again though, that's my belief. If you want to change it weekly that's your choice. There is a reason Toyota and many other manufacturers seal their transmissions and don't have a recommendation on brake fluid change interval, and it's not so components will fail. It's for reliability by keeping the "shade tree mechanics who think they know better than the OEM engineers" ignorant people out of the critical systems.
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nevada
Senior Member
moisture is only part of the problem.
brake fluid also deteriorates the metal in the system. you'll start getting microscopic metal particles, and this will lead to seals leaking, in the MC and abs systems.
2 years is best for a flush. you CAN get away with not doing it, but just like running a T-belt past its time, you're taking an unnecessary risk.
brake fluid also deteriorates the metal in the system. you'll start getting microscopic metal particles, and this will lead to seals leaking, in the MC and abs systems.
2 years is best for a flush. you CAN get away with not doing it, but just like running a T-belt past its time, you're taking an unnecessary risk.
ron in sc
New member
When brake system has moisture in it the boiling point of the fluid will be reached at a much lower temperature. That means brake fade or no brakes.
For example ATE typ 200 has a minimum boiling point of 536 degrees F. It has a wet boiling point of 388 degrees F.
My point is brakes are real important and I maintain mine in a manner that makes me feel safe.
However, my way is not the only way.
For example ATE typ 200 has a minimum boiling point of 536 degrees F. It has a wet boiling point of 388 degrees F.
My point is brakes are real important and I maintain mine in a manner that makes me feel safe.
However, my way is not the only way.
homeyclaus
New member
It's safe to say that there is more than one usage pattern, and depending on this, the fluid "ought to be" changed, and in some instances "must" be changed. When drawing up maintenance intervals, the engineers lack the crystal ball that tells them how you, yes you, will use your vehicle, so the use conservative numbers.
As it stands, most of my vehicles had their brake fluid changed every 4 years or so just by virtue of a caliper, piston, or hose needing to be changed. Given how hot vehicles run in some competition scenarios, I am impressed that the brake systems hold pressure for more than one season.
As it stands, most of my vehicles had their brake fluid changed every 4 years or so just by virtue of a caliper, piston, or hose needing to be changed. Given how hot vehicles run in some competition scenarios, I am impressed that the brake systems hold pressure for more than one season.
