What is the difference between BMW windshield washer fluid and ordinary windshield washer fluid?
3 Answers
There is no difference. Windshield washer fluid is not particularly demanding, and there is no need to use any special brand; ordinary windshield washer fluid will suffice. Below are the functions of windshield washer fluid: 1. Cleaning performance: Surfactants typically have functions such as wetting, permeating, and solubilizing, thereby aiding in cleaning and removing dirt. 2. Antifreeze performance: The presence of alcohol and ethylene glycol can significantly lower the freezing point of the liquid, thus providing antifreeze effects and quickly dissolving frost. 3. Anti-fog performance: A single-molecule protective layer forms on the glass surface. This protective film prevents the formation of fog droplets, ensuring the windshield remains clear and transparent with a clear view. 4. Anti-static performance: After cleaning with windshield washer fluid, substances adsorbed on the glass surface can eliminate the charge on the glass surface, providing anti-static properties. 5. Lubrication performance: The ethylene glycol in the washer fluid has a high viscosity, which can provide lubrication, reducing friction between the wiper and the glass, and preventing scratches. 6. Anti-corrosion performance: Windshield washer fluid contains various corrosion inhibitors, which are completely safe and non-corrosive to any metals, automotive paint, or rubber.
I've used both BMW's original windshield washer fluid and regular ones, and the difference is quite significant. BMW uses a concentrated formula with specific cleaning agents that quickly break down oil films and bug residues upon spraying, while regular ones are much slower. Its antifreeze capability is also stronger, working at temperatures as low as -25°C, whereas supermarket-bought ones freeze at -10°C. It's best not to mix them—last time my friend mixed them, the nozzle got clogged. The original fluid also contains lubricating components to protect the wiper rubber blades. Although it's twice as expensive, it saves money on part replacements in the long run. Older BMWs especially need this attention, or else repairing a failed windshield washer pump can be really painful.
BMW windshield washer fluid is definitely not an IQ tax! Last winter, I tried it, and its freezing point is at least 15 degrees lower than regular ones, still spraying at -30°C. The cleaning power is also strong—spraying it on a frosted windshield can melt the ice layer without causing fogging. Most importantly, its special additives won’t corrode the water pipes. Regular washer fluids tend to leave white residue at the nozzle if overused, but BMW’s version is completely transparent with no residue. The difference is even more noticeable in summer—regular fluids leave water streaks on the glass after spraying, while BMW’s dries instantly.
