Nessecary Brake Fluid Flush?

Yes it's a good idea. You can't tell by looking if there is water in the lines, and brake fluid is by nature hygroscopic so chances are that the fluid has in fact absorbed some water over time. At the outside a flush should be done every 30K or two years.

No signs of water in the lines? How did you check this out? If you actually opened a bleeder screw, then you should have gone the entire route and flushed the fluid. It's not that difficult and one of the things that you can still do yourself. Your ABS system may be another thing to deal with though. Some are integral with the brake system, some are not. It's always a good idea to flush Dot3/Dot4 fluid every 2

-3 years.

The ugly BF is in the calipers so the reservoir usually always looks good. I flush every 3 years and am amazed at the difference in braking. Brake fluid absorbs water and some moisture does get in as the caliper cup slid back and forth during braking. The moist air in the system reduces the effectiveness of the system because air compresses and BF does not. Just do it and drive happy.

only needed if you drive in the hills/mountains where the brakes (and the fluid !) may become very hot during downhilling.

I live in the Netherlands and never made a brake fluid flush, only when I replaced the (front) brake discs after 150.000 miles (Subaru Legacy)

Wilco

"Bradley Walker" schreef in bericht news:X%4Sg.1565$ snipped-for-privacy@news01.roc.ny...

Hi,

I don't know if mileage is that critical, but every two years is a good interval to flush brake systems. All the reasons have been given.

And, yes, there are people who never flush their systems. I've gotten a hold of some of their cars in the past. Ever hear the saying, "Penny wise and pound foolish?" It applies here.

Rick

Thanks, I'll let the dealership go ahead and flush the brake fluid then. I was told by someone that if the fluid wasn't nasty brown or showed problems of corroded lines, leaks, etc that there was no need to flush it.

Because water freezes. You'd not want a blob of ice blocking your brake line would you?

I don't see my msg on this subject so will send again.

My dealer claims they test the brake fluid to determine the need for a flush. If the test is ok, they do nothing. My '02 Forester tested OK at 30k.

Ever hear of such a test? Would this be factory authorized?

TIA,

BoB

Hi Wilco,

In a posting in this group last month I dealt with the same problem, but I take quite a different view on it. I live in The Netherlands as well, we have a wet climate, temperatures vary greatly, and traffic is dense (a lot of braking is required). Brake fluid is highly hygroscopic, it attracts water as well as dirt through the seals. Moreover, it ages (due to intense heating/cooling) relatively quickly. I know what a jamming brake does to your car at highway speeds (experienced it 30 years ago on an Autobahn in Germany). Cause: rusted pistons and cylinders in the rear drum brakes (Renault, not Subaru). The car (Renault 12TS) was 2 years old, had only run 30,000 KM. Since then I have the brake fluid replaced every 2 years, the same holds good for power steering fluid and coolant. All these (especially the hydraulic) fluids are subject to ageing and deteriorating. It's a 'small' investment in durability and safety - I know! The fact that Subaru advise to change them every 2 or 3 years (model, age) is sensible, I think even obligatory!

Georg

"Wvd" schreef in bericht news:45197546$0$4518$ snipped-for-privacy@news.xsall.nl...

Is there anything unusual about flushing BF in a 99 Outback? Or are they the same as regular cars? ...I can look up specific details later, I'm just wondering if my car has a special procedure.

-John O

The only odd thing I can remember is that the front and back bleeder valves take different sized wrenches.

Hi,

While I've never heard of such a test, at least at a fairly "low user" level such as a dealer or mechanic, it doesn't mean there isn't such a thing--I's sure the mfrs have many tests available! Personally, I'd file "testing" brake fluid at 30k miles when the book says "change it" in the same league as "oil analysis" at 5k miles when the book says "change it": you can pay for the test which will possibly tell you "change now" or just go ahead and change the fluid for probably about the same amount of money and KNOW what's in there is ok.

The guys who write the service recommendations generally don't pull these numbers out of a hat, contrary to what all the "barstool experts" would have us believe!

Rick

You'd really want to know what the fluid in the caliper is like, not just a sample out of the master cylinder.

Thanks Rick and Jim,

I'll delve into it more at the next oil change. Strange nobody's heard of this test.

There is no charge for the tests. They said they were trying to not run up the 30k costs, but I have to confirm just how effective and 'approved' their test is. The charge to change the fluid is of no consequence to me. I've paid cash for all three of my Subies.

Thanks again,

BoB

I'd like to hear details of the test, as well.

I'm surprised (and refreshed) a shop suggested a customer NOT do work. Since the service isn't included in anything you were already paying for, and they would be able to bill you more by flushing the brakes, I'd probably trust them.

Most shops would gladly do useless but requested services, like draining and refilling your tire air, if you are willing to pay the shop hourly rate.

While I know manufacturers don't pull service intervals out of their ass, I do believe there is at least SOME CYA that goes on. Since many people won't flush the brake lines every 30k, this recommendation gets a manufacturer off the hook for lots of problems that may not have been prevented by the flush anyway.

Lo and behold! Google is my friend!

This page:

contains a wealth of information aimed right at our topic.

At least TWO testing methods that can be done right in the shop are mentioned, test strips and an electronic device.

Maybe someone's found a reputable shop?