I know 'the book' says every 2 years or 30k, but is this actually necessary? I understand the water content of the fluid increases over time and anything over about 2-3% is too high (boils too easily and promotes corrision), but how long would this take to happen in a Scooby assuming the recommended DOT 3 is used? Also, does anybody know how I can measure the water content of said fluid without expensive equipment - I've heard about strips you can buy (dip in and match to a colour chart) but don't know where to get them?

 

change mine yearly, along with gearbox & axel oils.

Not a waste in mind, just an extra safty measure

 

I think brakes are one of those things you don't scrimp on!

Better safe than sorry and that sort of thing!