DOT 5.1
Encyclopedia
DOT 5.1 is one of several designations of automotive brake fluid
, denoting a particular mixture of chemicals imparting specified ranges of boiling point
.
A brake fluid's dry boiling point is the temperature at which the pure fluid will boil. Wet boiling point concerns the boiling temperature when the fluid contains water.
In the United States, all brake fluids must meet Standard No. 116; Motor vehicle brake fluids. Under this standard there are three Department of Transportation
(DOT) minimal specifications for brake fluid. They are DOT 3
, DOT 4
and DOT 5.1.
DOT 5.1, like DOT 3 and DOT 4, is a polyethylene glycol
-based fluid (contrasted with DOT 5
which is silicone
-based). Polyethylene glycol fluids are hygroscopic and will absorb water from the atmosphere, which is necessary to prevent sheer and undiluted water in the braking system, which is very corrosive, also water droplets can freeze in the pipes, thus blocking the system.
, most cars produced in the U.S. use DOT 4 brake fluid.
Brake fluid
Brake fluid is a type of hydraulic fluid used in hydraulic brake and hydraulic clutch applications in automobiles, motorcycles, light trucks, and some bicycles. It is used to transfer force into pressure...
, denoting a particular mixture of chemicals imparting specified ranges of boiling point
Boiling point
The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
.
A brake fluid's dry boiling point is the temperature at which the pure fluid will boil. Wet boiling point concerns the boiling temperature when the fluid contains water.
In the United States, all brake fluids must meet Standard No. 116; Motor vehicle brake fluids. Under this standard there are three Department of Transportation
United States Department of Transportation
The United States Department of Transportation is a federal Cabinet department of the United States government concerned with transportation. It was established by an act of Congress on October 15, 1966, and began operation on April 1, 1967...
(DOT) minimal specifications for brake fluid. They are DOT 3
DOT 3
DOT 3 is one of several designations of automotive brake fluid, denoting a particular mixture of chemicals imparting specified ranges of boiling point....
, DOT 4
DOT 4
DOT 4 is one of several designations of automotive brake fluid, denoting a particular mixture of chemicals imparting specified ranges of boiling point....
and DOT 5.1.
DOT 5.1, like DOT 3 and DOT 4, is a polyethylene glycol
Polyethylene glycol
Polyethylene glycol is a polyether compound with many applications from industrial manufacturing to medicine. It has also been known as polyethylene oxide or polyoxyethylene , depending on its molecular weight, and under the tradename Carbowax.-Available forms:PEG, PEO, or POE refers to an...
-based fluid (contrasted with DOT 5
DOT 5
DOT 5 is one of several designations of automotive hydraulic brake fluid, denoting a particular mixture of chemicals imparting specified ranges of boiling point.DOT 5 is a silicone-based brake fluid ....
which is silicone
Silicone
Silicones are inert, synthetic compounds with a variety of forms and uses. Typically heat-resistant and rubber-like, they are used in sealants, adhesives, lubricants, medical applications , cookware, and insulation....
-based). Polyethylene glycol fluids are hygroscopic and will absorb water from the atmosphere, which is necessary to prevent sheer and undiluted water in the braking system, which is very corrosive, also water droplets can freeze in the pipes, thus blocking the system.
, most cars produced in the U.S. use DOT 4 brake fluid.
Boiling points
Minimum boiling points for these specifications are as follows (wet boiling point defined as 3.7% water by volume):| Dry boiling point | Wet boiling point | |
|---|---|---|
| DOT 3 | 205 °C (401 °F) | 140 °C (284 °F) |
| DOT 4 | 230 °C (446 °F) | 155 °C (311 °F) |
| DOT 5 | 260 °C (500 °F) | 180 °C (356 °F) |
| DOT 5.1 | 260 °C (500 °F) | 180 °C (356 °F) |
| DOT 5 DOT 5 DOT 5 is one of several designations of automotive hydraulic brake fluid, denoting a particular mixture of chemicals imparting specified ranges of boiling point.DOT 5 is a silicone-based brake fluid .... |
Brake fluid Brake fluid Brake fluid is a type of hydraulic fluid used in hydraulic brake and hydraulic clutch applications in automobiles, motorcycles, light trucks, and some bicycles. It is used to transfer force into pressure... s |
None | ||
|---|---|---|---|---|