Brake Fluid Contamination

CAUTION: The hydraulic fluid used in automotive brake systems is hydroscopic. This means that the hydraulic fluid tends to absorb moisture from the atmosphere over periods of time. As hydraulic brake fluid absorbs moisture, it effects the function of the vehicles hydraulic brake system. For this reason the vehicles hydraulic brake fluid should be drained and replaced using fresh clean hydraulic brake fluid every two years. When replacing hydraulic brake fluid use only Mopar (R) brake fluid or an equivalent from a sealed container. Brake fluid must conform to DOT 3, specifications. See Brake Bleeding, Service and Repair for required bleeding procedures to be used for replacing hydraulic brake fluid.

Indications of fluid contamination are swollen or deteriorated rubber parts.
Swollen rubber parts indicate the presence of petroleum in the brake fluid.
To test for contamination, put small amount of drained brake fluid in clear glass jar. If fluid separates into layers, there is mineral oil contamination.
If contaminated, drain and thoroughly flush system. Replace master cylinder, proportioning valve, caliper seals and all hoses.