I have previously posted on a thread on here about the necessity (or not) to change brake fluid.

I know most (if not ALL) manufacturers "RECOMMEND" changing the brake fluid at specified intervals, but I have been servicing cars for 25 years now (albeit 20 of those as a "hobby"), and have yet to change the entire brake fluid on a car, and have never had anyone experience any problems whatsoever with their brake fluid.

I am aware that brake fluid absorbs moisture from the air, and after prolonged periods of heavy braking can actually boil, and that the brakes can fade due to excessive temperature build up, but am wondering whether anyone has actually experienced any problems with day-to-day use of their car (as opposed to racing/track days etc) due to not having changed their brake fluid ??.

I have been pondering this problem for a while, but it has been brought to a head today when a mate contacted the local BMW "stealer" to price up the first service on his '07 plate 330d, and was told that along with the oil and filter and cabin filter (yeah right !!), it also needed the brake fluid changing, and they were going to relieve him of £350 for the privelege !!!!!!!!

£350 doesn't sound bad for a BMW intermediate service and brake fluid change tbh.

Had plenty of lder VW's and the like with spongy brakes and a good fluid change sorts them out, especially the really old dirty ones. The water in the brake fluid compresses and the brake fuild does not so even if the brakes arent getting hot enough to boil the water and create pockets the water itself can still give a long pedal.

Yes I've had problems on NSL single carriageways with the brakes just being generally awful at less than 2 years old.

Fluid change and it felt much better and was proven by a long drive all the way through Germany and back a few days later.

What I will say is that modern cars are much heavier on the whole, so you seem to notice brake issues much more now as stopping 1.5Tonne is much harder than stopping 1Tonne.

TBH I have found that as the degredation is over a long period you only noitce the difference after you have changed it.

Well, I've had the brake fluid on mine changed twice now, neither time with any other brake work beyond maybe a manual handbrake adjustment, and the pedal felt firmer afterwards. I can't say I've ever felt the fluid boiling, but then I normally don't use the brakes, because all they do is slow you down!