Q: How often should brake fluid be changed?
A: This can be a tricky question and depends a lot upon who you are asking. European and some Japanese OEMs have a brake fluid service interval of two years or 24,000 miles. Nissan has an interval of 15,000 miles. Ford, Chrysler and GM provide no recommendation. Some shops say to change it when it looks dirty or smells funny. Others say to change it when moisture levels are high or when a brake part is replaced.
DOT FMVSS 116 standards state that new DOT 3 brake fluid should not have a wet boiling point below 284 degrees F, that it should protect a brake system from corrosion and meet a viscous specification.
Based upon a nationwide study of 469 vehicles, there is only a 1.3 percent chance that shops will find a vehicle with a wet boiling point below DOT standards. The same study found 48 percent of the vehicles tested do not meet the DOT corrosion standards.
The fastest, most reliable method to determine when a vehicle no longer meets DOT corrosion standards is to test for copper corrosion contamination. This can be done with a simple test strip. A copper test strip quickly reveals an increased opportunity for shops to offer a brake fluid exchange.
Information provided by: Phoenix Systems LLC
