All forms of brake fluid are given a DOT rating. DOT simply stands for Department of Transport, which sets the safety regulations for the acceptable performance of different brake fluids. The DOT ratings given to brake fluids are based on the liquid’s dry and wet boiling points.

Since DOT 4 and 5.1 are both glycol-based brake fluids they are compatible with each other, which means they can be readily mixed without harming your brake system.

Yes, the same. The clutch fluid is the same as brake fluid. You can add brake fluid to the clutch master cylinder. There’s no such thing individual clutch fluid.

Using the wrong fluid can cause poor lubrication, overheating, and possibly transmission failure. A mechanic might not be able to reverse the damage, even by flushing the transmission. Mistakenly adding motor oil or brake fluid can also destroy your transmission.

Brands do not matter. Brake fluid is rather simple in design. Dot 3,4, and 5.1 can all be mixed. The difference is, as the number increases, so does the boiling point of the fluid.

tl dr – Mixing Brand X fluid with Brand Y fluid is of no consequence, as long as you are mixing the same grade of fluid (DOT3, 4, 5, or 5.1). In order to be rated at a given grade, it must meet the prerequisites of the grade.

All DOT 3, 4 and 5.1 brake fluids are compatible with each other and with all systems. If you have an older vehicle and are worried about boiling the fluid, use DOT 4 or 5.1 brake fluid.

Q I see many brake fluids on the market are now synthetic DOT 3 or DOT 4. All DOT 3, DOT 4 and DOT 5.1 fluids (the numbers refer to U.S. Department of Transportation specifications) are conventional glycol/ester-based hydraulic fluids, meaning they can and will damage paint if spilled on automotive bodywork.

Pentosin DOT 4 LV is a special brake fluid of highest DOT 4 performance levels and extremely low viscosity at cold temperatures. Pentosin DOT 4 LV Brake Fluid is ideal for all modern vehicles with ESP and ABS. DOT 4 LV can be used in all vehicles that require DOT 4 fluid.

It has a lower boiling temperature (less performance) but does not attract moisture as much as it’s competition DOT 4. DOT 4 brake fluid has a higher boiling temperature (higher performance) but needs to be flushed and replaced more often.