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When did brake fluid flushing become a thing

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DavidApp

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Had my wife's car serviced today. Complementary service as we just purchased the car there a few months ago. When I picked it up they said that it is due for the brake fluid flush. It has 22,000 miles and is less than 2 years old. The service person explained this is to get the Air bubbles out of the brake lines.
Looking on line one explanation for needing the fluid flush is as the brakes wear bits of rotor get into the fluid and Must be flushed out.

Sounds like a solution looking for a problem at that stage in the car's life.

David
 
Sounds like a dealer special. The hydraulics on a car are a sealed system. How the heck are bits of the rotor supposed to get into the fluid?
 
My service place for my Ody tells me there is copper in the fluid from the lines degrading the fluid
 
I had a Toyota for 20+ years before getting rid of it for something newer. In that time other than topping it up occasionally, and that means I could count the times on one hand during that time period, I never did a flush and refill and never had a brake issue related to fluid.
 
Not much reason to expect ingress of anything into the hydraulics unless it'd be moisture. Moisture will corrode the cylinder bores and steel lines, so any water avid brake fluids should be "flushed", usually on an annual schedule. But with the advent of synthetic fluids that seems a remote possibility. More likely the shops are looking to prop up lagging sales at the front-end (sales department).
DNK said:
My service place for my Ody tells me there is copper in the fluid from the lines degrading the fluid
Click to expand...
Suspect you mean the fluid degrades the copper lines. Sounds dubious to moi. Copper-nickel (90%-10%) brake lines are pretty much impervious to any modern brake fluids. Again, I call B.S. sales booster.

IMHO, only cause for flushing a modern system would be degrading of the seals, from wear over a period of time. Discoloration of the fluid would be an indicator.
 
Usually when I hear that I pull out most of the fluid out of the container and put in new.
That keeps the wolfs away for a while
 
My old 1986Ford Ranger pickup has over 200,000 miles on it and the brake fluid has never been flushed! Been off the road and only used on the place for the past 10 years, but everything still works. Brake fluid flush sounds like the old shock absorber oil squirt trick!
DNK said:
My service place for my Ody tells me there is copper in the fluid from the lines degrading the fluid
Click to expand...
LOL, That's a new one on me! That's funny!
 
And don't forget the annual air change in your tires...
 
hmmm - wonder if anyone still just follows the maintenance schedule issued by the manufacturers. When I take my (leased) Nissan in for free scheduled maintenance (fluids, tire rotation, etc.), service rep always says other things are needed (transmission fluid change, brake fluid change, brake pads change, etc.).

Seems we could just look in the owner's manual and decide what needs doin'. Doubt the dealer's service tech knows more than the manufacturers.

Just sayin' ...

Tom M.
 
Seams a pretty bogus story line from the shops. As Doc said most of us believe it is important to keep any condensed water out of the system but I must confess I don’t even do that. And I to have driven many daily drivers for 10 to 15 years and never touched the brakes except for pads. Some of my professional mechanic friends have told me that even when they have to change a caliper they will do everything they can to minimize loss of fluid mostly because of environmental concerns with disposal. I have seen more than one YouTube video that has shown what they claim is a change of fluid. They suck the fluid out of the reservoir and then refill the reservoir with new fluid. If that is what they call a change of fluid it is a cheat and a rip off. What about the rest of the fluid in the system and that does nothing to displace air and water.
 
vette said:
I have seen more than one YouTube video that has shown what they claim is a change of fluid. They suck the fluid out of the reservoir and then refill the reservoir with new fluid. If that is what they call a change of fluid it is a cheat and a rip off. What about the rest of the fluid in the system and that does nothing to displace air and water.
Click to expand...

Seen that as well. We've serviced many different cars over the years, hydraulic systems ranging from single-cylinder ones to the Rolls mineral oil, high pressure type. Any time the fluids were in question, the entire system was flushed. About the only recurrent issue was from vehicles that were sitting static for long periods. Moisture avid fluid will then cause corrosion around seals not changing their position in a steel bore. In many cases the flexible lines will deteriorate as well, acting as "valves" to allow pressure only one way, leading to lock-up of the brakes. With most of the "classic" cars we've seen with pitted cylinder bores, we've had them sleeved with stainless liners. One time expense for "lifetime" brake hydraulics.
 
There is no way there should be any little bubbles getting into your brake system. that would indicate a problem somewhere. Bad seal, rusted line, or some other breech of the system. There is also no possible way bits of the rotor could ever get into the brake fluid either. Both of those lines are uneducated BS.
The only reasons for a flush would be breakdown of the fluid due to thermal cycling, age, or moisture contamination.
If you live in a hilly area and tend to run through brake pads quickly, have a high performance car you like to drive the way it was made to drive, or have a truck you do a lot of hauling with then eventually a flush is gonna be a good thing to do, and it will help save problems in a very expensive ABS module, but I think that the brake flush service is over sold in most cases. It's an easy hour added to a flat-rate technicians paycheck/ billable shop time. And if a salesman wants to try and get you to buy that service they should at least understand the real reason for doing it.
 
Banjo said:
. And if a salesman wants to try and get you to buy that service they should at least understand the real reason for doing it.
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Right on, Bro.
 
The Healey doesn't have a sealed system. The stock seal for the reservoir is just a rubber washer and the cap has a hole in it.
 
I'd be curious the "flushing" procedure. Drain and refill with new... or drain, FLUSH, and refill with new?
 
I replace res. fluid yearly with start up and never changed with new pads just had to remove some fluid when collapsing pistons. I live in a dry area so I do not think of moisture I would guess some of my brake fluid is over 25 years old. Even when I replaced the Master cyl only added to as need for system. Newer cars do get more heat but then they use DOT 5. Madflyer
 
Talking to a friend in Richmond VA an mentioned the fluid flush. He said he has his done every year because that is what the dealer says has to be done to maintain his warrantee. And it is only $195.00 a year plus you get Free fluid top up at service time.

He was always one to fall for a line of BS.

David
 
Popeye said:
I'd be curious the "flushing" procedure. Drain and refill with new... or drain, FLUSH, and refill with new?
Click to expand...

Maybe the term "flush" is a bit exaggerated. The procedure most commonly applied is to bleed the system using fresh fluid, starting with the longest length wheel cylinder (or caliper) line and work new fluid through the system until it comes out that end, then do the same at each progressively closer cylinder. The only "flushing" done would be if a system has been sitting open for some length of time, with the possibility of air/moisture/corroding of the lines. Then it would be prudent to "flush" lines (NOT master cylinder or slave devices) with denatured alcohol and follow immediately with high pressure air to purge them. A fairly rare scenario.

GregW said:
The Healey doesn't have a sealed system. The stock seal for the reservoir is just a rubber washer and the cap has a hole in it.
Click to expand...

Most of our LBC's are the same. And fluids contemporary with them were much more moisture avid. A high humidity (we're talkin' British here, remember) environment would tend to contaminate the fluid, hence the "annual" fluid replacement suggestion. To repurpose an old Cali adage: "If it's yellow, let it mellow. If it's brown, flush it down." Dark brake fluid is an indicator of an issue. For the sake of safety a system with less-that clear fluid should be looked at as having some sort of contamination and investigated. Starting with a fluid change. Those of us with single-stage master cylinders may want to be a bit more diligent about it, too. Or "a fair bit of pedal stabbing" could result. Along with a change of undergarments after the fact. :eek:
 
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Popeye said:
I'd be curious the "flushing" procedure. Drain and refill with new... or drain, FLUSH, and refill with new?
Click to expand...
The dealer I worked for had a Wagner brake fluid flush machine. I had several hoses coming out of a vacuum can and a pressurized fresh fluid supply.
We would hook the fluid supply to the top of the reservoir on the master cylinder, put the hoses over the bleeders on all 4 wheels and open the bleeders. then turn on the machine and wait for the fluid coming out to look cleaner. It really did change out nearly all the fluid in the system.
When done properly and for the right reasons it's a legit service, but as I stated before, I think often it is sold when not needed just to make the billable shop hours look better.
I didn't use that machine very often. Only if, like Doc said, I opened a system to find dark nasty looking fluid.
the other part of that is around here, being snugly in the middle of the rust belt, often times bleeders break off when trying to open them. Now a quick easy job just became a time consuming, potentially expensive PITA.
 
I suspect billable hours - but also manufacturers CYA. The car is an accident and ends up in court. "I'm sorry your honour the plaintiff didn't follow the factory recommendations for maintenance."
 
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