Brake Fluid change - rogerb
I have a Focus tdi Zetec, with ABS, just coming up to 2yrs old & 30k miles.

I drive quite a lot on urban roads, but am fairly light on the brakes - still comfortably on my 1st set of pads.

When do you experts recommend that I renew my brake fluid ?

Thanks in advance :-)
Re: Brake Fluid change - David W

Your light use has no effect on the need to change the fluid.

It's due now as a sensible maintenance precaution.

Re: Brake Fluid change - me
you can have it tested for percentage of moisture, and make a scientific decision based on that... pretty simple test
Brake Fluid change - David Lacey
Change it Roger, it will only cost about £25ish, including the fluid. I take it the car will be going into the nearest Dealer for servicing? It should be changed as part of the service schedule at 2yrs old, surely?

Re: Brake Fluid change - Bob H
"you can have it tested for percentage of moisture, and make a scientific decision based on that... pretty simple test"

How do you test? and what is the allowable percentage?

By the way what exactly is the effect of too high a percentage of moisture -brake fade? corrosion problems?

I always have it changed in accordance with the Service Schedule but have the nagging suspicion that it is a candidate for one of those garage scams highlighted by HJ a few weeks ago.
Re: Brake Fluid change - John Davis
Bob. Most brake fluids are hydroscopic, ie, they attract moisture from the air but, there are some synthetic types which do not. Any moisture, within the fluid, lowers its overall boiling point and, usually, this water content will boil at the hottest part of the braking system, ie, the discs/calipers. The water was not compressible but, the resulting vapour, trapped in the system, is. In extreme circumstances, ie, heavy and prolonged braking, the vapour content, within the hydraulic system, produced by the boiling of the water, will allow the brake pedal to travel to the floor before any hydraulic pressure reaches the brake actuating cylinders. Some garages have the equipment which takes a small sample of fluid, artificially heats it, and measures the resulting boiling point. Brake fluid containers should never be left open and exposed to the atmosphere, nor should old fluid be used in modern, high temperature brakes. Vehicle manufacturers do recommend that brake fluid is changed periodically, for this very reason. The phenomenon never appeared on, say, Morris Minors with drum brakes, but, when disc brakes started to become quite common, with non vented discs etc, the resulting high temperatures revealed this potentially fatal flaw. Quite a few years ago, following a number of unexplained accidents where the vehicle brakes were found to be perfect when the hydraulic system was cold, on the heating test, the fluid was found to "boil" after a simulated run in moderate traffic, of only a couple of miles.
Re: Brake Fluid change - Andrew Hamilton
Some garages never seem to change brake fluid. My mothers old mini had brake fluid leaks and MOT failure due to corroded pistons and cylinders. It is so easy to change. I use a pressurised thing that uses spare tyre pressure on a filler bottle so none of the press and hold required on footbrake.
Re: Brake Fluid change - rogerb
Thanks for your help.

Are there any other 'little jobs' I should consider, about now, which might 'Prolong Active Life' ? (as the ad used to say)
The car's, that is, not mine!
Re: Brake Fluid change - Andrew Tarr
HJ will tell you to change coolant and brake fluid every 2 years. The interesting thing is that some manufacturers (e.g.Renault) don't even mention a coolant change interval, and some Renault dealers therefore never change it. So you find Clios with something like gravy circulating in the waterways.
Re: Brake Fluid change - Derek
This is an interesting thread. I have a Peugeot 406 HDi company car, which I am considering buying when its lease expires. Therefore, I am getting the oil changed at 6000 mile intervals, even though the handbook says 12000 (thank you, HJ). At my cost, obviously.

My wife took delivery of a Pug 206 petrol last Saturday and I was amazed to see that major services, including oil changes, are 20000 miles! According to the dealer, it's because semi-synthetics enable them to do this.

It begs the question, if the manufacturers are deferring oil changes beyond, in my opinion, a reasonable period, what else are they misleading us about?
Re: Brake Fluid change - John Slaughter

The answer is that they are trying to keep servicing costs to a minimum to sell cars to fleets in the UK. These long service intervals don't apply in mainland europe, or in the USA. In the US they seem to think 6k miles is a long time between oil changes. Fleet owners usually ignore things like 2 year brake fluid changes and just do the minimum.

Privately owned cars are not necessarily better, as many private owners think servicing is an option and ignore the 'or one/two year' bit of the servicing recommendation.

So, fleets are happy, but second owners get the problems.


Re: Brake Fluid change - John Davis
Full marks John for that explanation. Yes, it's a marketing exercise to artificially defer some of the inevitable maintenance and financial burdens from the unwary vehicle owner. Even with the best made vehicles, 20,000 miles with no knowledgeable technician taking a look underneath or at what is falling off or has been damaged in use, is, sometimes, a disaster waiting to happen.
Re: Brake Fluid change - ROBIN
In fact though,with modern cars,nearly nothing ever DOES fall off.
I dont like the extended oil change intervals one little bit,but I would very much like to see a 6 month servicing requirement,with oil change.
I think we need to get away from mileage related anything and move to an hours/time system of servicing,together with lifed parts that are automatically
replaced at set intervals.Rolls Royce were heading this way,but the nearest available service book is 300 miles away so I cant check!
I dont think it would hurt if the Mot was far wider ranging and also included all bodywork.
Here in Cornwall there are an awful lot of belching multicolored heaps with very dodgy suspension,so something must be wrong with the inspection system.
Or perhaps its just that the police are just as obsessed here with annoying motorists trying to keep the traffic moving rather than actually doing something positive about road safety.I've seen the same car with only one headlight and an illegal lump of bodywork for 3 weeks now,if he ever exceeds a speed limit he'll be dead meat....

Value my car