Replacing brake fluid

Someone once told me that it was a good idea to replace your brake fluid regularly, because of its hygroscopic nature and that the water build up will corode the brake system.

When I replaced the wheel cylinders on and old Beetle, the recon ones I fitted were resleeved with stainless steel, which should not have this problem. Is this necessary with the E36 BMWs, brake and clutch, and how often do I need to have it done.

Reply to
MW de Jager
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Not just because it corrodes the system, but as the water content increases your brake fluid will (obviously) dilute, meaning that if you had to do some heavy braking, there is a chance your fluid will boil and you'll lose all braking capability.

By all means do the stainless steel thing if you can, but you still need to replace the fluid regularly to keep yourself in one piece!

Reply to
zerouali

wheras the cylinders were stainless, the rest of the hydraulic system may not be... pipes, pistons, springs etc... change the fluid at the recomneded intervals... every 2 years if memory serves. in areas of high humidity, I would do it more often.

- less so in dry places. it isnt a huge job and bad brakes kill ppl.

keith

Reply to
keith

Someone was partly right. The brake fluid is hygroscopic (absorbs moisture) and it is a very good idea to change it on a regular basis, but not because it will corrode the innards of the brake system. Even if you filled your brake lines with straight water it would not corrode in there in the absence of oxygen.

The reason to replace the fluid is because as the fluid absorbs water it lowers its boiling point. Under heavy braking (coming down out of mountain pass, etc.) the fluid may boil and cause the brakes to fade when you need them most (avoid falling off the big precipice?)

General rule of thumb is every 2 years. I suppose it should really vary depending on how much ambient humidity it will be subjected to. Those folks living in Phoenix could probably safely double that interval.

YMMV,

-Fred W

Reply to
Malt_Hound

I've just spoken to the local stealer, and according to my car's service record it is due for a major service at which stage they replace all fluids anyway. My motor mac will obviously do the service for half the price.

Anyone know CASTROL SG/SF specification motor oil. Is this good enough for my 328i?

Regards MW

Reply to
MW de Jager

Brake Fluid change is not included in an Ins 2 , they are charged additional. same for coolant + cabin filters are your own discretion.

Reply to
trollgeddon

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