What does dot mean in brakes?
Department of Transport
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.
Which is better DOT 4 or dot 5 brake fluid?
However, DOT 5 is a silicon based fluid, which means its not practical for constant use because silicon does not absorb moisture. Any moisture will remain as water and corrode metal parts, and since no brake system is truly “sealed,” the fluid requires more frequent changes. DOT 4 is a glycol based fluid which is hygroscopic (water absorbing).
Can you mix dot 5 with DOT 4 glycol?
Krikket & Glider have it right exactly…DO NOT MIX SILICONE BASED DOT 5 with GLYCOL BASED DOT 4 EVER!!! DOT 4 is the highest temp rating for Glycol (old technology brake fluid) used primarily in Disc brake systems; DOT 3 was used in older Drum brake systems…think automotive technology here.
Is it bad to mix brake fluid in 1987 FXRS?
Check the cap on the cylinder, it should tell you or the owners or factory manual will tell you also. YES, mixing is VERY bad. In my 1987 fxrs it says right on the master cylinder caps DOT 5 only. DOT 5 is standard for that year. Most, if not all, after market brake parts for that year are DOT 5.
Can you use DOT 5 on a paint job?
DOT 5 does not destroy your paint job as DOT 3 would… DOT 5 was originally introduced as a racing brake fluid due to its very high boiling point. However, DOT 5 is a silicon based fluid, which means its not practical for constant use because silicon does not absorb moisture.
What kind of brake fluid does a road King use?
My 2003 Road King clearly states on the front master cylinder that DOT 5 brake fluid should be used, as does my Clymer shop manual. When I opened the front master cylinder, the brake fluid was Amber in color (not purple as DOT 5 brake fluid should be).
Which is better dot 3 or dot 5 brake fluid?
Earlier this month the question of Dot 3 vs Dot 5 came up here on the forum. Dot 3 & Dot 4 are Gycol based brake fluid & Dot 5 is a silicone based fluid. If we introduce Dot 5 Silicone to a Dot 3-4 Glycol base the Silicone will literally float apart from the Gycol.
What kind of brake fluid is on front master cylinder?
When I opened the front master cylinder, the brake fluid was Amber in color (not purple as DOT 5 brake fluid should be). With old eyes, I added DOT 4 brake fluid to top off the front master cylinder and only later did I notice the DOT 5 message on the master cylinder.
Can you use DOT 5 on DOT 3 glycol?
If we introduce Dot 5 Silicone to a Dot 3-4 Glycol base the Silicone will literally float apart from the Gycol. Their chemical structure inhibits them from ever becoming compatible & as a matter a fact the Silicone used in Dot 5 can & will attack any rubber component which is not compatible with the chemical structure of the Silicone based fluid.