Windshield washer fluid can be homemade according to seasonal needs. The basic formula is 2 litres of purified water mixed with 250 ml of 95% medical-grade alcohol and 1-2 capfuls of dishwashing liquid, suitable for routine cleaning. During summer when insect residues are abundant, the alcohol content may be increased to 500 ml to enhance dissolving capacity, though note that high alcohol concentration may accelerate wiper blade deterioration. For winter antifreeze purposes, a 20% alcohol to 80% water mixture is advised, with a freezing point around -10°C. However, in extremely cold regions, purchasing professional antifreeze windshield fluid remains recommended for safety. While homemade solutions are cost-effective (approximately 5-10 MYR per 2.5 litres), commercial windshield fluids (about 15-30 MYR per bottle) offer superior corrosion protection, wiper lubrication, and low-temperature performance, proving more advantageous for long-term vehicle maintenance.
