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| Brake Fluid Check |
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Automotive brake fluid is formulated to meet standards developed by the
Department of Transportation (DOT) and the Society of Automotive Engineers.
The Department of Transportation assigns a number indicating the fluid rating:
DOT3, DOT4, DOT5. The higher the number the higher the boiling point.
Brake fluid is either silicon or glycol based. Never mix the two and always use
the type of fluid recommended for the vehicle your working on. Another thing to
remember is that glycol based brake fluid will damage paint and should be
handled accordingly.
As mentioned earlier the higher the DOT number the higher the boiling point.
This is important because heat generated from friction is transferred from the
braking system to the brake fluid. This heat can cause the brake fluid to boil
producing vapor.
A hydraulic braking system works because fluids are not compressible. The
problem with brake fluid is when it boils it converts to a vapor. This vapor is
compressible and will result in reduced braking performance or worse. A brake
system flush with the proper brake fluid is necessary to remedy this condition.
Most of today's vehicles use DOT3 glycol (Polyalkylene Glycol Ether) type brake
fluid. Silicon based fluids (DOT5) are usually found in special applications like
show cars because it doesn't damage painted surfaces like it's glycol
counterpart.
All brake fluids must meet DOT standards for corrosion protection, lubrication,
boiling point and more.
Department of Transportation (DOT) and the Society of Automotive Engineers.
The Department of Transportation assigns a number indicating the fluid rating:
DOT3, DOT4, DOT5. The higher the number the higher the boiling point.
Brake fluid is either silicon or glycol based. Never mix the two and always use
the type of fluid recommended for the vehicle your working on. Another thing to
remember is that glycol based brake fluid will damage paint and should be
handled accordingly.
As mentioned earlier the higher the DOT number the higher the boiling point.
This is important because heat generated from friction is transferred from the
braking system to the brake fluid. This heat can cause the brake fluid to boil
producing vapor.
A hydraulic braking system works because fluids are not compressible. The
problem with brake fluid is when it boils it converts to a vapor. This vapor is
compressible and will result in reduced braking performance or worse. A brake
system flush with the proper brake fluid is necessary to remedy this condition.
Most of today's vehicles use DOT3 glycol (Polyalkylene Glycol Ether) type brake
fluid. Silicon based fluids (DOT5) are usually found in special applications like
show cars because it doesn't damage painted surfaces like it's glycol
counterpart.
All brake fluids must meet DOT standards for corrosion protection, lubrication,
boiling point and more.