Brake Fluid Change. How often?

[nc35]

Hi All

I know the service manual and the stickers say every two years, but service delta don't seem bothered.

Just booked wifes car in for first service @ two years with only 7k on the clock. Service guy didn't think fluid change was needed.
I have got him to add it to the service for £25 which I didn't think was bad.

Thought DOT4 fluid absorbes water.

Can anyone shed light on this?

Cheers

Lee

[Janner_Sy]

25 quid is an absolute bargain for brake fluid change. 

[DaveB@Vagbremtechnic]

Dont worry about dot 4 or 5 its just a specification, an OEM quality Dot 4 will be much better than a Halfords Dot 5.

If the OEM stuff is indeed dot4 then it might be something freaky such as the freezing viscosity level that might not meet the Dot5 specs it will be better than your average Dot 5 you just cant use it in Alaska in winter!

Its also worth a mention that the Mk5 OEM stuff is also used on a ceramic braked V10 R8 - it comes into "if it aint broke" category imvho of course if you're boiling it off on track days then RBF the way even then just bleeding out the stuff that got hot would go a long way.

The £25 fixed cost thing is a bloody bargain, get a load of guys complaining of a soft pedal after spending hundreds on a BBK and then installing it on the driveway......The Dealer OEM bleed is a good option to sort it, the SEAT dealers also know what they're doing with four pots

[Janner_Sy]

must admit i boiledmine at the ring, although the fluid had been in the car since new at that point. (2 years)  at the end of the ring i could pretty muich do 3/4 of the brake pedal with no effect . 

[nc35]

Thanks for your replies.

As per your answer is top notch Dave glad you saw the post.

Is it true that the fluid absorbs water over time hence needing the change?

[Janner_Sy]

thats the reason for the two year change

[DaveB@Vagbremtechnic]

Thanks for your replies.

As per your answer is top notch Dave glad you saw the post.

Is it true that the fluid absorbs water over time hence needing the change?

Yep its Hygroscopic, nearly all mineral oils do over time. We change our Hydraulic fluid in our airplane every 1000 hours so roughly two years, theres mil spec stuff which isn't used much anymore called Skydrol that resists water absorption  but its frickin nasty stuff you'll probably still have it in chinooks and the loadies'l be telling you to avoid stepping in it as it'll melt your boots! 

PS Dont put "aquired" skydrol in you're Octy     

[Janner_Sy]

it wouldnt be stolen or aquired. we refer to it as redistribution of essential eqiuipment.

[Merlinman]

 

First brake fluid change is now at 3 years not two - get your dealer to confirm.

[DaveB@Vagbremtechnic]

it wouldnt be stolen or aquired. we refer to it as redistribution of essential eqiuipment.

 

[Tarmac_Terrorist]

I don't undertand why the initial brake fluid change is now recommended at 3 years instead of 2, but then every two years thereafter??

I assume it's the same spec fluid that dealers use as it is at the factory.

[gillm]

i do mine every year or before a track day . and i use comma 5.1

[FamilyDub]

25 quid is an absolute bargain for brake fluid change. 

^^^ +1. Excellent price.

I paid £35 from an independent VAG specialist for the fluid for OEM stuff, as a comparison?

[Tfsi_Mike]

25 quid is an absolute bargain for brake fluid change. 

^^^ +1. Excellent price.

I paid £35 from an independent VAG specialist for the fluid for OEM stuff, as a comparison?

£30 quid for fitting my goodridge hoses & changing my brake fluid was a bargain for me