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Brake fluid attracts moisture, brake fluid is very corrosive, heat effects the fluid just as it would any oil/fluid.

There is a valid reason to keep it fresh every two years, if you do not adhere to the recommended schedules for service PAG may deny a warranty claim in your brake system due to service neglect.

Its under $300 at the dealer and its then documented in their system, I could have changed mine myself last year, but it would not have been noted in the Porsche system as to the date and mileage it was performed, so I had them do it so that it was documented.

Some things you just get done, its a upfront cost to ensure a down the road warranty on the brake system.
My SA at my dealer says I can send her the detail on any maintenance I perform and they will update it in their system. I've not done anything on the Macan yet so we'll see if she's true to her word. No way I'm paying $350 to flush brake fluid when I have a Quick Jack and a Motive Brake Bleeder setup and have done many brake flushes myself.
 
A query into the necessity of brake fluid flushing. I wouldn't do this on my Macan but I have a 2005 Ford F-150. I've never flushed the brake fluid. instead once a year I'll remove the old fluid in the resevoir, careful not to expose the master cylinter to air and refill with fresh brake fluid. My thoughts are that the new fluid works itself into all the components, and how often you do this, using a baster/syringe kitchen tool, determines the amount of contamination of old fluid in the system. It's so easy and Dot 3 fluid is cheap.
 
A query into the necessity of brake fluid flushing. I wouldn't do this on my Macan but I have a 2005 Ford F-150. I've never flushed the brake fluid. instead once a year I'll remove the old fluid in the resevoir, careful not to expose the master cylinter to air and refill with fresh brake fluid. My thoughts are that the new fluid works itself into all the components, and how often you do this, using a baster/syringe kitchen tool, determines the amount of contamination of old fluid in the system. It's so easy and Dot 3 fluid is cheap.

That method would be the same as sucking 1/4 of your engine oil out, not changing the filter and putting only 1/4 of fresh oil back into the system.

When the rubber seals in the calipers go bad, and the system is compromised due to moisture the exchange of that small quantity of fluid is not doing much to remove contaminants and moisture.

There are reasons why service is recommended, its not because the manufacturers want you to spend money for no reason, its called maintaining your vehicle.

This is not my opinion, its done for the long term reliability of the braking system.

Think of a glass of milk, you put a small amount of chocolate syrup in that glass, the whole entire color of the milk changes, same thing with brake fluid, you just added clean fluid to dirty and contaminated fluid, its not doing much to mitigate the reasons for changing it.
 
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A query into the necessity of brake fluid flushing. I wouldn't do this on my Macan but I have a 2005 Ford F-150. I've never flushed the brake fluid. instead once a year I'll remove the old fluid in the resevoir, careful not to expose the master cylinter to air and refill with fresh brake fluid. My thoughts are that the new fluid works itself into all the components, and how often you do this, using a baster/syringe kitchen tool, determines the amount of contamination of old fluid in the system. It's so easy and Dot 3 fluid is cheap.

This method works for me. I do it quite often before the old fluid goes bad. It is easy and quick and sufficient for non-demanding driving/environment.
 
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My guesstimate is that I'm replacing at least 75% of the brake fluid when refilling the resevoir (my Ford F-150 has a deep resevoir) and that there is a complete tranfer of the new fluid (now mixed with the old remaining fluid at 25%) through out the entire system. Do it again a few months later and you have a high proportion of good brake fluid in the system. As I stated earlier I wouldn't do it on my Macan, but I'm curious to others opinions on this method as I seems to work for my truck.
 
I do this on my Macan, which has a big brake fluid reservoir.

In fact, Macan/Porsche is no different from most other cars for oil change and brake fluid change, etc. No secrets here at all.
 
I power bleed my Corvettes, its quite simple, suck all the master cylinder fluid out first and replace with clean fluid.


I then bleed the drivers front first, as that empties the master cylinder quickest, then I go to the pass front, drivers rear and passenger rear last.

That is the opposite of what I usually do for a bleed, but with a pressure MOTIV Power bleeder it makes it quick, if I go to the right rear first its a waste of more fluid IMHO than going to the closest and working back to the farthest.

I have a lift and am able to remove all four wheels easily, as my Corvettes have dual bleeders as they apply pressure from both the inside and outside and do not have a standard caliper in which only one side applies pressure and the other side gets pulled not applied.

Its not hard or expensive to do, its about Porsche knowing it was done, its about them not being able to deny warranty
 
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Easy to check the moisture content.

It is the contaminants that concern me. Is this a real vs imagined issue?

IDK but, until I read definitive evidence that moisture is the sole issue, I will be paying to flush brake system in my cars.

The question for me is how often?

I flat out do not believe 2 years, regardless of mileage is true. I think the manufacturers do not want to make it complicated.
My best guess is it may be much longer for dry climates & shorter for damp climates.

When you bring in your car for a $100-200 brake fluid flush, I doubt many mechanics are going to tell you: "I tested your fluid & you do not need this service yet."

If I lived in a humid climate, I'd want to test to see how much moisture is in there @ 1 year. Maybe need to flush every 1 year?
 
A query into the necessity of brake fluid flushing. I wouldn't do this on my Macan but I have a 2005 Ford F-150. I've never flushed the brake fluid. instead once a year I'll remove the old fluid in the resevoir, careful not to expose the master cylinter to air and refill with fresh brake fluid. My thoughts are that the new fluid works itself into all the components, and how often you do this, using a baster/syringe kitchen tool, determines the amount of contamination of old fluid in the system. It's so easy and Dot 3 fluid is cheap.
Maybe I'm the only one that has worked on old cars but the steel lines rust from the inside out and that's due to water.
 
I bleed brakes on all my cars. Pretty easy and cheap. dot 3 and 4 is the same and is very cheap. The hardest part is taking the wheels off. I save the receipts in case of warranty work for all my service I do myself. Here is a link to a DIY I posted with a 911. Same procedure. You can buy different kinds of bleeder tool at harbor freight really cheap to. I do every two years and the pedal usually feels a little firmer to me with the new fluid. BTW I know people with 100K and never changed fluid, LOL. Not me, I drive a Porsche because I like cars, so cheap and easy service is a no brainer.
https://www.6speedonline.com/forums/997/276985-diy-997-2-brake-fluid-flush.html#post3555600
 
A query into the necessity of brake fluid flushing. I wouldn't do this on my Macan but I have a 2005 Ford F-150. I've never flushed the brake fluid. instead once a year I'll remove the old fluid in the reservoir, careful not to expose the master cylinder to air and refill with fresh brake fluid. My thoughts are that the new fluid works itself into all the components, and how often you do this, using a baster/syringe kitchen tool, determines the amount of contamination of old fluid in the system. It's so easy and Dot 3 fluid is cheap.
I'm sure your happy with your process. And you can do anything that you like. And I polity and respectfully suggest that you do a little more research.

I see a brake system that is closed. There is no line return from the end of the caliper, back to the master cylinder and reservoir. So changing the fluid in the holding tank has zero effect in all the pipes below. I change the fluid out as required from the manual. I think 300+ is too expensive. Pay that if you like. My indy charges @ 100 buck, within my visit of oil change, pdk fluid change etc.

In my 8o's Honda/Michelin days, I used to bleed my brakes between races. Turn the wheel, crack the bolt, it pissed out 3 feet. Top off the reservoir.
It went in the reservoir clean and clear apple juice colour and came out the caliper discoloured and bubbly. Solid rotor on the front, drums in the back. Brakes were good for another 6 minutes, before the peddle went, @##%# oh ship, to the floor.
 

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This topic has been debated extensively before.

The brake fluid system is a closed system but is also connected, meaning all the fluid is in one connected system, so the fresh fluid in the brake master cylinder/reservoir works its way throughout the whole system, perhaps slowly.

Otherwise, why would there be a brake fluid reservoir at all?
 
This topic has been debated extensively before.

The brake fluid system is a closed system but is also connected, meaning all the fluid is in one connected system, so the fresh fluid in the brake master cylinder/reservoir works its way throughout the whole system, perhaps slowly.

Otherwise, why would there be a brake fluid reservoir at all?
As the brake pads wear the pistons in the caliper move further out increasing the volume of fluid required in the system. Also rotor wear adds to the requirement for more fluid in the calipers.

There is no return line from any of the 4 calipers back to the master cylinder or the reservoir, how is new fluid from the reservoir getting swapped with old fluid in the calipers?
 
It’s called diffusion as long as the fluid in the system is connected.

I have noticed fresh fluid in the reservoir gets dark/dirty after a while. Then you just keep exchanging the fluid in the reservoir with new fluid and it will stay clean after a few cycles.

It’s easy to do and everyone can do it without using any tools. It may not be as thorough as bleeding but it works.
 
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Diffusion, l have difficulty believing it would be possible for the new fluid in the master cylinder to travel through brake lines and hoses with an internal diameter of maybe 1/16” and make it all the way through the lines, through the abs unit, through to the calipers ,from one side of the caliper to the other side of the caliper ( front) or all the way to the rear caliper, maybe 4 meters of brake line and back to the master cylinder to exchange new for old fluid. Yeah, right.
 
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