Citroen Brake Fluid for Sale in South Africa

DOT 4 across the modern range — C3, Xsara, C3 Aircross, C5 and C5 Aircross all take it, and the manufacturer's own documentation confirms it. The one thing never to do is fit DOT 5, which is silicone-based rather than glycol-based. It is not compatible with the seals in an ABS system and it will not mix with what is already in the car. DOT 5.1, confusingly, is glycol-based and is compatible — but there is no reason to use it in a road car.

Every two years, or 40,000 to 60,000 km, whichever arrives first — and the time limit is the one that matters, because fluid absorbs moisture whether the car is driven or parked. Coastal owners in Durban or along the KZN north coast should treat two years as a firm ceiling regardless of how low the mileage is. This is the cheapest safety-related service on the car and the one most often skipped.

The fluid itself is inexpensive. DOT 4 comes in 500 ml bottles, with budget brands around R65.86 and Castrol around R99, and a full system flush needs more than one bottle. The cost is the labour — allow about an hour for a proper four-corner bleed. The sensible move is to have it done at the same time as a pad or disc change, since the brakes are already apart and much of the labour overlaps.

They are both glycol-based, so they will mix without any chemical drama. The problem is that the mixture takes on the lower of the two boiling points, so topping a DOT 4 system up with DOT 3 quietly reduces the fade resistance of the whole system. In an emergency, to get home, it is better than driving on a low reservoir. As a plan, it is not — flush the system and refill with fresh DOT 4.

A pedal that goes soft on a long descent is the one that matters, because that is moisture in the fluid boiling under heat. Alongside that: fluid gone dark instead of pale straw, and ABS intervening sooner than it used to in the wet. You do not have to guess at any of this — a test strip or an electronic moisture tester takes seconds at any workshop and gives you a water percentage rather than an opinion.