Brake fluid change

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Thu 10 Mar 2016 16:10
Brake fluid change - Doc

What is the current view on brake fluid changes?

Most handbooks seem to specify every 2 years. Could this be safely extended to 3 years?

In the distant past, I never changed the fluid, except when topping-up after work on the hydraulic system.

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Thu 10 Mar 2016 16:27
Brake fluid change - craig-pd130

Most manufacturers state every 2 years, but it is always charged as an extra on top of routine servicing.

You can buy LED brake fluid testers for less than £10 from eBay which indicate the level of water contamination in the brake fluid.

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Thu 10 Mar 2016 17:13
Brake fluid change - John F

What is the current view on brake fluid changes?

Most handbooks seem to specify every 2 years. Could this be safely extended to 3 years?

In the distant past, I never changed the fluid, except when topping up after work.......

Good for you! The handbook advice is yet another example of the motor industry creating as much work as it can. Unless you are using silicone DoT 5, where any attracted water separates, drains to the bottom and rots things, I think at least 5yrs is reasonable unless you regularly drive down Alps towing a caravan. For most people, even if their brake fluid got so 'wet' that its boiling point of 230C was halved, they would still be unlikely ever to boil it.

I see from my records our 2000 Focus possibly had it changed in 2007 when it required a new rear brake cylinder when a rear bearing (a known fault on Mk1 Foci) was replaced. I might change it this summer. The way we drive I suspect merely good old Bluecol antifreeze (boiling point 165C) would suffice!

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Thu 10 Mar 2016 19:51
Brake fluid change - dimdip

I feel a certain sense of Deja-Vu here, but doesn't the possibility of corrosion at the calipers merit a mention?

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Thu 10 Mar 2016 20:41
Brake fluid change - gordonbennet

Its such an easy job i don't get why there's such a palarva about timelines, every year for many or at the every most every other year the pads should be removed and the calipers cleaned exercised and lubed before re-assembly, whilst doing this it takes 2 minutes more per wheel to bleed the caliper out at the same time, cost possibly 10 minutes total extra for changing the fluid (including syphoning the old out of the master cyl reservior) and maybe £10 of fluid at the absolute maximum, so why not do it.

The benefits to doing it regularly include never finding a seized bleed nipple and keeping the fluid clean in the hidden depths of the system all the time, win win.

Course its in the main dealers interests to make it sound like a massive operation, but its not its just another additional part of proper brake maintenance and should be included for a nominal fee of say £30 when the brakes are serviced.

Couple of highlights i recall from my kerbside cowboy days for examples of brake neglect...

Renault in for service, brake pads worn down to metal for God knows how long (how did they not hear/feel the racket?), both solid front discs worn down to literally a tiny fraction of an inch, roughly 1/16" thick at best, how they didn't shatter causing total failure i shall never know.

Citroen 2CV, front pad missing completely, the aluminium piston had been acting as the friction material, worn into the shape of French Foreign Legion cap, so much of that piston worn away that another few brake applications and the piston would have given way and come out, again total brake failure imminent.

More recently we found the parking brake shoe lining completely detached on my sons S60 Volvo, s'ok they all do that sir its a safety feature, luckily it hadn't picked up which can lock the rear hub @ £££...and on a Benz i bought once the rear pad friction material was only held in place by the clump of rust on the backing plate, previous owners oblivious to what was going on underneath...but don't worry the paintwork was really shiny on both..:-)

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Thu 10 Mar 2016 20:57
Brake fluid change - Wackyracer

We are talking about brakes, safety should come before a bit of penny misering surely?

I can't understand it myself, if you DIY the cost is under a fiver. It only takes a few mins with a vacuum bleeder and not much longer if you do it the old fashioned way. False economy not to, seized calipers and wheel cylinders cost alot more than fluid.

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Fri 11 Mar 2016 09:21
Brake fluid change - John F

I can't understand it myself, if you DIY the cost is under a fiver.

Well, try to understand it from the point of view of an elderly person with only the state pension and meagre savings with no DIY expertise who only does around 3,000m a year. There will be nothing unsafe about their 5yr old brake fluid. Corrosion of wheel cylinders/calipers will be highly unlikely.

My 1980 TR7 front calipers are original and its rear cylinders lasted more than twenty years.

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Fri 11 Mar 2016 10:30
Brake fluid change - slkfanboy

>My 1980 TR7 front calipers are original and its rear cylinders lasted more than twenty years.

well lets hope the brake fliud is not also the orginal, else you will not be needing that state pension any more.

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Fri 11 Mar 2016 12:17
Brake fluid change - Peter.N.

I am a 76 year old elderly person who still does all his own car repairs but to be fair I have done them all my life.

I must confess that in 50 years of motoring I have never done a brake fluid change, not intentionally any way, if I have had a brake problem I have flushed it through but have never had a problem due to not changing the fluid.

I'm not suggesting that it shouldn't be done, probably just that I am lazy and only do things that are essential like oil changes and repairs to anything that doesn't function as it should.

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Fri 11 Mar 2016 15:40
Brake fluid change - galileo

Having replaced wheel cylinders and calipers on a number of the banger I had (before I could afford better cars) I have obviously topped up the master cylinder when bleeding the system, so probably replaced most of the fluid anyway, but never replaced fluid for the sake of doing so.

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Sat 12 Mar 2016 09:40
Brake fluid change - hardway

Many valid points here,

My own opinion/worry is the amount of rear wheel cylinder I've had to renew over the years.

And pretty much all of them because of rust inside where the pistons sit.

Usually siezed solid.

And I've never seen a service schedule that ststes "Remove the wheel cylinder pistons and check for rust"

So the only way to at least try to prevent this is with a full fluid flush.

Same thing can happen with rear callipers,

Again who removes calliper pistons to check inside?

Not something normaly done.

I consider servicing as something done to prevent big bills for the owner further down the line as much as maintaning the vehicle reliability.

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Sat 12 Mar 2016 10:37
Brake fluid change - Peter.N.

I have unstuck many a sticky caliper by lifting up the rubber seal and squirting brake fluid in so that it runs right round the piston, if it wont free off by itself take the pads out and put a tyre lever in and get someone to operate the pedal, work it backwards and forwards a few times, never failed yet. I keep a small oil can with brake fluid in it for the purpose.

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Sat 12 Mar 2016 14:29
Brake fluid change - bathtub tom

if it wont free off by itself take the pads out and put a tyre lever in and get someone to operate the pedal, work it backwards and forwards a few times

You'll likely end up with a buckled disc doing this.

My experience taught me to bleed the brakes each year, mainly because of the black fluid that was expelled from the cast iron rear wheel cylinders.

I don't know if cast iron reacts differently to brake fluid compared with other materials, but I've only ever had to replace rear wheel cylinders in fifty years.

Anyone who's ever experienced brake fluid boiling will probably replace the fluid regularly - I've experienced it once!

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Sat 12 Mar 2016 11:02
Brake fluid change - John F

>My 1980 TR7 front calipers are original and its rear cylinders lasted more than twenty years.

well lets hope the brake fliud is not also the orginal, else you will not be needing that state pension any more.

Rest assured, s'boy. My records show I changed it in 1989, then again in 2000 when I serviced the seals on a leaky o/s rear cylinder, and again in 2010 when I had both rear cyclinders replaced professionally. I might change it again in 2020 if it and I are still on the road.

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Sat 12 Mar 2016 18:49
Brake fluid change - John Boy

I think there's now more emphasis on this because some ABS pumps seem to fail due to corrosion, presumably from water in the brake fluid. Whether the pumps are replaced or repaired, the cost makes £30 for a fluid change seem like a very cheap insurance policy. That's how I look at it anyway.

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Sat 12 Mar 2016 20:37
Brake fluid change - Wackyracer

I think there's now more emphasis on this because some ABS pumps seem to fail due to corrosion, presumably from water in the brake fluid. Whether the pumps are replaced or repaired, the cost makes £30 for a fluid change seem like a very cheap insurance policy. That's how I look at it anyway.

Not a bad insurance policy at around 4pence a day, based on changing it every 24months.

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Sat 12 Mar 2016 23:25
Brake fluid change - edlithgow

I used to operate (in the uk) on an "if it ain't broke" basis and got away with it, only replacing fluid if I was forced to work on the brakes. Perhaps the previous owners of my UK bangers had been more pro-active.

My old Taiwanese car is teaching me different.

I've learned the hard way that brake fluid deteriorates, that when it does the system can fail quite suddenly, and suffers from corrosion, and once the corrosion has happened brake flushing won't necessarily remove it.

The turkey baster has the advantage that, on a neglected system, you can use it to remove accumulated sludge from the bottom of the master cylinder reservoir, though disassembly is probably indicated in that case.

For flushing I've found gravity or a syringe are both easier and safer than using the brake pedal, and don't involve the purchase of gizmos that are probably not available here anyway.

The syringe is alleged to carry a risk of reversing master cylinder seals. So far so good, touch wood.

I'm thinking maybe dismantling one corner a year (with the associated partial drain) might be a practical maintenance regime, but at the moment I'm still in the damage control phase.

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