Hi,

I apologise for my ignorance in advance.

Just the other day i noticed that on my door sticker on the bottom brake fluid change is marked for 2026, which means after 2 years.

My car is 2024 Superb MK 3 / 2.0 TDI DSG.(Made on 25th of October 2023).

Never heard of brake fluid change before, never changed it and no service shop ever mentioned it......EVER ( I'm 62 years old and owned cars since I was 18). I was always checking brake fluid level, same as service people, and that was it.

Can someone enlighten me about what is "new" about brake fluid and why?

Thanks

Edited 18 January18 Jan by ZJZ
Grammar

Nothing new about Manufacturers recommendations about Brake Fluid Changes. As for VW / Skoda it was First @ 2 years then each 2 up to about 2011, then changed to first @ 3 years then each 2. Then about 3 years ago they changed it back to firsat at 2 years then each 2. Really something of a little earner for Main Dealerships. But it is their recommendation, guidelines, schedule, advice.......

4 minutes ago, Evolution13 said:

Nothing new about Manufacturers recommendations about Brake Fluid Changes. As for VW / Skoda it was First @ 2 years then each 2 up to about 2011, then changed to first @ 3 years then each 2. Then about 3 years ago they changed it back to firsat at 2 years then each 2. Really something of a little earner for Main Dealerships. But it is their recommendation, guidelines, schedule, advice.......

The thing is, just my last three cars were VW , Skoda, octavia and now Superb. All bought new. All three in,warranty period, were serviced at authorised dealer shops. None of them ever ,even mentioned brake fluid. Also after warranty expires I was going to "my" mechanic. He also never mentioned it 🫤. Strange

How often do you change it?

That is what you get with rubbish training of Service Staff at Main Dealerships. On job training from somebody who knows little about cars or servicing and maintenance. I do not change fluid on new cars i have no longer than a few years but with an old / used cars when upgrading brakes the fluid is changed. I have had 15 Motability cars, all got the brake fluid changed before 3 years old and the MOT, before hand back. Part of the Servicing. The last 3 EV,s i have had have had the Brake fluid changed @ 2 years old. Skoda had a chart like this 2018-2021. Not accurate, but gives an idea...

Edited 18 January18 Jan by Evolution13

It can be tested for water content

Edited 18 January18 Jan by Stonekeeper

8 minutes ago, Stonekeeper said:

It can be tested for water content

Nice video, thanks.

So it turns out that I was lucky, so far. Never changed brake fluid and never had even the slightest problems with my brakes, even on 10 year old cars. When they hit 10 years they were sold anyway.

Thou I was always replacing my brake pads, and discs if needed, mostly before their time. Also calipers checked and looked for any leaks anywhere.

It seems, when everything is replaced early and checked thoroughly brake system acts as hermeticaly closed system so water and dirt can't come in.

At least , that's the only explanation I can come up with.

As I said, in 45 years, never raplaced brake fluid and never had the slightest problem.

Edited 18 January18 Jan by ZJZ

1994 Washington State Fatality: A major accident investigation (M.A.I.T.) documented a fatal collision involving a five-year-old minivan with 79,000 miles. The vehicle, though well-maintained mechanically, suffered a sudden loss of brake pressure. Investigators determined the cause was vaporization of the brake fluid due to accumulated moisture, which lowered its boiling point below the operating temperatures reached during the mountain descent.

https://baonghean.vn/en/nguy-co-tai-nan-tu-dau-phanh-nhiem-nuoc-10170011.html

I am not sure if it's still the case but West Mercia / West Midlands police use to test brake fluid in cars to check the condition of the break fluid.

A garage can test the condition of the break fluid with a simple test.

3 minutes ago, Stonekeeper said:

1994 Washington State Fatality: A major accident investigation (M.A.I.T.) documented a fatal collision involving a five-year-old minivan with 79,000 miles. The vehicle, though well-maintained mechanically, suffered a sudden loss of brake pressure. Investigators determined the cause was vaporization of the brake fluid due to accumulated moisture, which lowered its boiling point below the operating temperatures reached during the mountain descent.

What about the air in the brake system?

How dangerous that is?

Edited 18 January18 Jan by ZJZ

4 hours ago, ZJZ said:

Never heard of brake fluid change before, never changed it and no service shop ever mentioned it

They probably didn't it but never told you (or you didn't hear correctly)

1 hour ago, ZJZ said:

What about the air in the brake system?

How dangerous that is?

A bit. But you don't run with air in it.

2 hours ago, ZJZ said:

they hit 10 years they were sold anyway

Probably fine for 10 yrs...the poor soul who inherited your car may have cursed you as the corrosion started to dominate their brake system

2 hours ago, ZJZ said:

system acts as hermeticaly closed system

It's not closed. Still absorbs moisture at the master cylinder...

As you said, we never changed it in the past but that was to the detriment of our cars a bit.

Not a heap, but Id change it at least every 5 yrs.

Doubt it will actually ever boil due to moisture but the corrosion would be a thing for me

1 minute ago, BlueWagon said:

They probably didn't it but never told you (or you didn't hear correctly)

A bit. But you don't run with air in it.

Probably fine for 10 yrs...the poor soul who inherited your car may have cursed you as the corrosion started to dominate their brake system

It's not closed. Still absorbs moisture at the master cylinder...

As you said, we never changed it in the past but that was to the detriment of our cars a bit.

Not a heap, but Id change it at least every 5 yrs.

Doubt it will actually ever boil due to moisture but the corrosion would be a thing for me

No they never changed it under warranty scheduled services at dealership, they would gladly charge me but it was never listed on a receipt.

I am asking about air , cause I'm wondering how much air can come in the brake system by unqualified mechanics handling fluid change. That is my concern

Edited 18 January18 Jan by ZJZ

16 minutes ago, ZJZ said:

how much air can come in the brake system by unqualified mechanics handling fluid change

None if you follow the procedure. Pretty sure you just keep the res full and draw the fluid off the lower parts.

36 minutes ago, ZJZ said:

No they never changed it under warranty scheduled services at dealership, they would gladly charge me but it was never listed on a receipt.

I am asking about air , cause I'm wondering how much air can come in the brake system by unqualified mechanics handling fluid change. That is my concern

Main Dealers or professional mechanic have pressurized system to replace brake fluid, so that there can't be air pushed in the system.

If needed, here is a "how to" about brake fluid replacement. 😉

You think you had no problem in several years of ownership. It may looked so, but for sure, very progressively other all these years, your brake systems on any of your cars had lose their efficiency which lengthens stopping distance.

Each time I replace my brake fluid after 2 years, the difference is noticeable. Brake pedal is firmer more quickly.

Just have your brake fluid replaced and you'll see. 😉

1 hour ago, BlueWagon said:

None if you follow the procedure. Pretty sure you just keep the res full and draw the fluid off the lower parts.

Not me, dealership service should follow the procedure, car is still warranty and service needs to be done by them.

For the last year they were unable to fix my windshield wipers , so now you know why I'm very concerned about "following the procedure"

1 hour ago, Bap33 said:

Main Dealers or professional mechanic have pressurized system to replace brake fluid, so that there can't be air pushed in the system.

If needed, here is a "how to" about brake fluid replacement. 😉

You think you had no problem in several years of ownership. It may looked so, but for sure, very progressively other all these years, your brake systems on any of your cars had lose their efficiency which lengthens stopping distance.

Each time I replace my brake fluid after 2 years, the difference is noticeable. Brake pedal is firmer more quickly.

Just have your brake fluid replaced and you'll see. 😉

Several years? Last car was bought new and sold when 10 years old. Believe me , I notice things while driving for which mechanics need one hour to find even when I point to them where the problem might be, and in 99% I was right.

I would have noticed if my brake pedal have changed for a milimeter.

I'm not saying you are wrong, at contrary and far from it, just saying my experience with cars I had.

Edited 19 January19 Jan by ZJZ

3 hours ago, ZJZ said:

I would have noticed if my brake pedal have changed for a milimeter.

Yeah alright guv....pull the other one 😀

If you don't want to change the brake fluid, don't.

Not a good idea but totally up to you

9 hours ago, ZJZ said:

No they never changed it under warranty scheduled services at dealership, they would gladly charge me but it was never listed on a receipt.

I am asking about air , cause I'm wondering how much air can come in the brake system by unqualified mechanics handling fluid change. That is my concern

Spotting air in the braking system is very easy - the pedal will be 'spongy'

Next time you check the Brake Fluid for H20 ain the reservoir, also then check the brake fluid you let out at the calipers if bleeding and see if there is the same content. PS Water in brake fluid, maybe never noticed, but driving spirited, sporting, lots of heat in the brake system then that water boils. Sooner than usual even not if ever on a track the XDS / XDS+ will disable its self. Also brake fade. And there is corrosion in brake pipes and calipers.

Edited 19 January19 Jan by Evolution13

@dsgman Good that some Police Force's vehicles are serviced and the 'Brake' fluid checked or changed. There are forces ion the UK and certainly regions of Scotland with Police Scotland vehicles where servicing is terrible, and vehicles not even MOT,d. But the MOT thing can be true anyplace in the UK with Police vehicles.

7 hours ago, ZJZ said:

I would have noticed if my brake pedal have changed for a milimeter.

You certainly have a great car experience, I won’t discuss it, but the quote above IS the point indeed. From day to day over 2 years, you don’t notice anything, because it’s soooo progressive. But once changed, your first words are just: wow! Not a bad thing, I had the brake fluid replaced.

Just have a look to my ´how to´ and compare old / new brake fluid color.

But it’s up to you. Not my car, not my passengers. 🤷‍♂️

42 minutes ago, Bap33 said:

You certainly have a great car experience, I won’t discuss it, but the quote above IS the point indeed. From day to day over 2 years, you don’t notice anything, because it’s soooo progressive. But once changed, your first words are just: wow! Not a bad thing, I had the brake fluid replaced.

Just have a look to my ´how to´ and compare old / new brake fluid color.

But it’s up to you. Not my car, not my passengers. 🤷‍♂️

Oh, misunderstanding. Of course I'll change it, just dont have confidence in authorised dealer shops. Because of warranty it's required to be done only by them.

Edited 19 January19 Jan by ZJZ

This is why, once warranty is over, I do all the maintenance that I can do myself… 😉

46 minutes ago, Bap33 said:

This is why, once warranty is over, I do all the maintenance that I can do myself… 😉

I wish I had a garage ........and knowlege to do it myself 😁

It has become more important now because of the change of fluids used.

Back in the day, as they say, replacing linings and bleeding the brakes afterwards was probably sufficient to return the fluid to a safe condition.

Nowadays brake linings seem to last longer, especially evs, and water getting in to the system by absorption effects the fluid differently, instead of dilution in dot3 and dot4 it separates out in dot5.

You will probably not notice it's happening until you need your brakes in an emergency or prolonged braking.

Gambling not to service it is a personal choice.