Good shout. It's not just the colour that's the problem, coolants lose their corrosion inhibiting properties over time, which is the main reason for the three year interval.

Brake fluid changes are another often neglected area. Just like the coolant looking clear and a pretty colour in the expansion tank, brake fluid can look equally clean and clear in the reservoir/inspection window. However, lurking in the depths of the pipework, the master cylinder and in the calipers it can be a horrible murky mess and full of moisture, which is a brake system's worst enemy.

So change you brake fluid too, particularly if you have no idea when it was last done...

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