The answer is, at 275 degrees F.
Brake fluid should have low freezing point
It means that the brake fluid absorbs water. Most all brake fluids you use in you're vehicles, automotive or otherwise will absorb water from the atmosphere right through the brake systems metal and rubber parts. You should change or at the very least, inspect your brake fluids yearly. As water is absorbed into the system, the boiling point lowers and the fluid can do very nasty things to your brake lines, abs systems and master cylinder parts.
No, it has to be higher.
the average boiling point of the brake fluid has dropped to a potentially dangerous level because of moisture contamination and may not meet minimum federal requirements for brake fluid.
the average boiling point of the brake fluid has dropped to a potentially dangerous level because of moisture contamination and may not meet minimum federal requirements for brake fluid.
brake fluid absorbs moisture thus brings the boiling point of your brake fluid down to a much lower temperature. if your brake fluid reaches this temperature you can loose your brakes temporally. also the moisture in the fluid will cause highly unwanted corrosion of internal parts of your brake system.
Flash point is the temperature at which a combustible material begins to give off enough vapors that it can be ignited with a spark. Pour point is the temperature at which a viscous fluid will flow easily, primarily used to indicate the ability to pump the fluid.
If your brake fluid is hygroscopic then it means that is will absorb water/moisture from the air and it can effect your boiling point and your brakes may fail at high speeds.
Anywhere from 420 to 480 F depending on brand and makeup.
Check your brake fluid.
It is recommended that brake fluid be added if it is low. We usually see marks on the dipstick (on vehicles that have them) or on the side of the brake fluid reservoir. The marks will usually say "full" or "low" and can be used as indicators as to if and when to add brake fluid. There is one more thing. Manufacturers and service professionals usually recommended that brake fluid be changed every two years. Brake fluid is hygroscopic, which means it absorbs water. If brake fluid absorbs atmospheric moisture over a period of time, the boiling point of the fluid will drop. Under extreme conditions, the fluid could boil causing catastrophic failure of the brakes.
Inspect the fluid level in the brake master cylinder reservoir. If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed from the reservoir before proceeding. If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding. Raise the vehicle and suitably support. Refer to Vehicle Lifting. Mark the relationship of the wheel to the hub flange. Remove the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation.