It's corrosion in the ABS system that will cause the biggest expense eventually. I wouldn't miss out on my brake fluid changes on either my Merc or my 206cc. On my old Corsa I change it every 5 years but that hasn't got ABS.
As others have said, why skimp on something that costs 1/2 a tank of fuel or less? False economy i.m.o.
Ron
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I would change my brake fluid myself, but it is too difficult in my experience. If the fluid needs changing on a VW as often as the oil, why not make is easier to do?
If water can get into the brake fluid, why doesn't the fluid leak out?
I have checked my Golf manual and the fluid on a new car does not need to be changed until the car is THREE years old.
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The Old Man`s 85 Polo C, had the same brake fluid in for 17yrs. He would never allow it to be changed.
Nothing rusted up or seized, one rear wheel cylinder was changed early on, but that was it.
He never drove it with the disks and drums glowing red hot though, so vaporisation was never tested.
I`m not supporting that, just reporting in as his `mechanic` over 17yrs and around 115,000 miles.
Edited by oilrag on 31/05/2008 at 15:59
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Just to add, The Old Man`s Polo always passed its MOT on brakes and they were as good, firm pedal etc, at 17 years as they were new.
Perhaps new generation driving, never use the gears to slow down, would make it more critical though.
At the top of that big hill from the North York Moors, dropping very steeply towards Whitby, ( where the use low gear sign is) cars blast past me at 80mph, then brake hard and all the way down. Brake gear must be cherry red by the bottom, but if you enter the hill at 25mph in third, you need only touch the braked lightly, once or twice on the way down.
I need convincing about ABS pumps being ruined too as there`s an old Golf nearby with ABS , that`s never had a fluid change or any problems too.
Edited by oilrag on 31/05/2008 at 16:15
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I'm also totally unconvinced about VW's recommendations or brake fluid change every 2 years. Although I understand people doing that if their rules say it invalidates warranty if you don't.
Certainly in USA there seem to be a lot of web sources which indicate 2 yearly brake fluid changes are less of a concern than over in Europe, and the brake fluid can't be that different - if at all different. I get mine changed only when having new pads / pads & discs, which is about every 5 years.
1) Wikipedia: en.wikipedia.org/wiki/Brake_fluid
"Changing fluid on a regular basis will greatly increase the performance of the brake system, but this is often not a concern in passenger cars. On the other hand, changing fluid at least every several years will preserve the life of brake system components (by removing accumulated water and other contaminants, thereby reducing rust on internal components), and increase the overall reliability of the brake system."
2) Phoenix Systems: www.brakestrips.net/tech_myth_stopper.htm
"Then there's the mistaken belief, now earning the distinction of ?urban legend,? that water is brake fluid's worst enemy and the slightest trace of it demands an immediate system flush or dire things might happen. So ingrained is this unwarranted fear, many costly flushes are needlessly performed and any unused fluid promptly discarded lest it absorb water while awaiting a future top-off.
Now, new technology and standards are finally putting the decades-old moisture myth to rest. Especially since today's Anti-Lock Brake Systems and brake fluids are designed to reduce or eliminate moisture related problems. In fact, GM, Ford and Chrysler have no recommendation for brake fluid service based on moisture because it's not considered a safety threat or service issue."
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I suspect American driving conditions (roads, speed limits) are VERY different from those in Europe. After all US cars long ago stopped being anywhere near teh forefront of technology.
If you have to go go a long 1 mile hill braking all the way with a hairpin at the bottom - not uncommon in the Peak District or Scotland... brake fuid temperatures become interesting...
I've had brake fade.. never again...change all brake fluids every two years.. easy DIY..
cost £6...
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Lets not forget that the primary cause of brake fade is overheating the friction material on the pads/shoes, rather than boiling the brake fluid.
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I suspect American driving conditions (roads speed limits) are VERY different from those in Europe.
There's plenty enough areas of the US with steep hills, and of course the cars being mainly automatics and the drivers probably being completely unaware of downshifting to slow the car, then the brakes will get a lot of work.
I remember that brake fluid used to be flash point tested but in manufacturer brake tests the fluid never reached the temperatures at which change was recommended.
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You might be interested in this article, which indicates the reason behind changing fluid is to maintain corrosion inhibition. Precis: over time etc - additive consumed - copper ions from the brake line brazing alloys released - corrosion accelerates - ABS at risk.
Link: www.babcox.com/editorial/bf/bf50412.htm
Apparently there is a test strip, in the US at least - to detect whether copper is kept below 200ppm, as an early warning of corrosion inhibitor performance.
Seems to eliminate the moisture issue, and explains the reasoning/ importance of maintaining the brake fluid quality. Perhaps a scientifically qualified reader could comment?
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Right, now I'm confused.
I fully admit I'm taking a very relaxed attitude to my Golf, because it was brand new when I got it, still under warranty, and is on a lease that includes maintenance. So, if there are funny noises I just pop it back to VW, but apart from that, I just wait for it to tell me it wants a service before booking it in proactively for anything. (Rest assured I'm not completely stupid - I do all the normal checks like oil and tyres.)
It's 2 years old in July and had it's first service at 19,000 and isn't going to ask for the next one until the end of this year.
Is it going to tell me it wants it's brake fluid changed, or do I need to remember and book it in?
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Is it going to tell me it wants it's brake fluid changed or do I need to remember and book it in?
There won't be a reminder but I would imagine it ought to be considered (by VW) to be OK until the next service (or they should have realised the interval at the last service and done it then.
On my MB on variable servicing it wasn't done until 3yrs and there was no comment about it - in fact I'd just bought a MB servicing package and they paid, even though strictly speaking it should have already been done.
Interesting that most manufacturers insist on 2yrs but our Honda Jazz has a 3yr BF change interval.
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to detect whether copper is kept below 200ppm, as an early warning of corrosion inhibitor performance.
Is this why manufacturers do not fit KuNiFer piping as standard?
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Could this explain why I've bled 'black syrup' (out of the rear cylinders mostly) of many of the old cars I've had. Particularly BL.
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The "black syrup" is likely to be the same as you get in domestic central heating systems : iron oxide...
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Report indicated it was the brazing material containing copper: implying steel tubing. Not knowing anything much on this subject, I looked up Kunifer. From copper.org: .... in 1976, Volvo adopted copper-nickel alloy C70600.....Users of copper-nickel brake tubing in addition to Volvo include world-class vehicle manufacturers like Rolls Royce, Lotus, Aston Martin, Porsche and, most recently, Audi. Copper-nickel is also used in military, fire fighting and other heavy vehicles."
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The term 'Kunifer' is derived from CuNiFe, an alloy of copper (Cu), nickel (Ni) and iron (Fe). How much of each I don't know.
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Report indicated it was the brazing material containing copper
Interesting report in Babcox, in that it is aimed at the US auto-servicing industry and the report's intention is to provide reasons for recommending a brake-fluid change to customers - [... customer makes a statement such as: "Nobody else has ever told me I should change my brake fluid." You will have to be prepared for this and include the necessary information to educate your customer as to the need and what you are basing it on. ]
Clearly it seems that in the US the aim is to persuade the customer to change the fluid based on test results, probably because in the absence of such tests the customers rely on "Statements made by the "Big 3" domestic OEM manufacturers that the brake fluid in their vehicles lasts the life of the vehicle". When taking in the implications of that statement by manufacturers, be aware that in the US:
1. the average life of a vehicle is much much longer than that of the average life of a vehicle in the UK.
2. the huge legal bills that the 3 big manufacturers would be risking if their advice to customers was deficient. It would be so easy for them to say "change every 2 or 3 years", yet they say there is no need to change for the life of the vehicle!
Also, note that the report fails to give any examples of problems caused in the braking systems of any of the few vehicles where they found the copper corrosion.
Finally, I know people who have had the same cars for 10 years or more without ever changing the brake fluid [indeed I know of one which has not had its brake fluid changed for 15 years] and remain safe to drive.
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I'm confused now as to whether it's 2 or 3 years before it needs changing, I also bought my car from new in '06, and what prompted me to think about it was that I received a card from my dealer inviting me to book it in for it's first b/f change after exactly 2 years.
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I'm confused now as to whether it's 2 or 3 years before it needs changing
Strictly speaking you really ought to follow whatever it says in the Service book.
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It says in the service book, after the first 3 years.
It says in the service book, after the first 3 years.
It says in the service book, after the first 3 years.
Sorry I forgot, when should you change your brake fluid in a VW?
Who cares, what does it matter, a good driver doesn't need brakes.
I have read the rotten Golf book, which tells you to change the brake fluid after the first 3 years. What is this after 3 years or 1 year or never.
If anybody is still confused, you should change the brake fluid after the first 3 years on a VW.
I am going to lie down now and think of brake fluids.
DOT4 or DOT5?
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I'm confused now as to whether it's 2 or 3 years before it needs changing
IMO, you could leave it for much longer without coming to any harm.
As I read it, the tests reported in Babcox link show that no ill effects were found due to the lowering of the boiling point from moisture ingress in to the system. The only proven effect was some evidence of corrosion of copper-alloy based components, but again no ill-effects on braking efficacy/efficiency were shown.
Unless someone can provide evidence to the contrary.
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The copper traces in the report were suggested as a precursor to other, heavier corrosion, potentially affecting the operation of the brake system. The idea is prevention - replace the brake fluid before the system is defective. As the report says, follow the mfrs guidelines, in addition to monitoring for signs of contamination. Or just wait until you need the brakes, then find they are AWOL, which is a little late in the day.
Edited by nortones2 on 01/06/2008 at 21:46
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'05 Service schedule - both Longlife and Time/distance-travelled intervals
"If the brake fluid is left in the system for too long, heavy use of the brakes may cause a vapour lock. This could cause the brakes to fail.
The brake fluid service must be carried out every two years.
The brake fluid service must be carried out at the stipulated time."
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Rudedog and colinh:
On page 1 of the Golf mk 5 service schedule 1.1 it says,
Brake fluid change
First change after 3 years, then every 2 years
(we recommend genuine Volkswagen brake fluid)
I have the service book in front of me, so let's be clear it says,
First change after 3 years. THREE YEARS.
It also gives the same advice in my Passat service book, which is to CHANGE THE BRAKE FLUID AFTER 3 YEARS, THEN EVERY 2 YEARS.
I hope this will kill this boring thread once and for all.
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There must have been a change for later models - my 1.1 service schedule for a Golf V delivered in August '05 shows "after 2 years" on page 1 (twice), page 8, page 9 and page 13 - THREE YEARS NOT MENTIONED.
I will grant that this is for a Golf delivered in Spain, but it is the English version of the manual.
Noting the fluid change cost ?13.06 in materials, and ?14.83 for 0.5 hours of labour, I will comment no further
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Every time you brake 4 pistons pop out of their resting place inside the calliper body and apply the brake pads to the disks retarding speed, as we know the pads touching the disks causes dust. Sometimes in our fine country it rains, the tyres pick up the rain complete with dirt and other contaminents from the road and sprays it under the wheel arches,all over the disks, callipers, etc
Everytime the brakes are released the pistons return home inside the calliper body, to prevent rain, dirt and brake dust entering the callipers there is an outer dust seal which stops 99.999% of what you don't want going into the hydraulic brake system (dirt ,dust, water etc) but life being life 0.001% does actually bypass the outer dust seal and reside between the outer dust seal and the hydraulic seal between the calliper and the piston. Life being life means the piston seal is only 99.999% efficient and allows a small amount of fluid out and the dust, dirt and water in. After many 1000s of applications of the brakes the fluid is dirty and water contaminated and need changing.
The master cylinder reservoir cap has a small hole in the top to prevent the reservoir "vacuuming", this hole allows tiny amounts of moisture into the reservoir contaminating the fluid and it needs changing.
Brakes, its only when you really need them do you find out exactly how good they are.
(The above discription is for a typical modern braking system, some systems may differ)
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