Rampant
Senior Member
Brake Fluid.
Okay, so I've spent the last couple hours [drinking beer and] researching the different types of brake fluids and what aspects are important to look at. I'm just going to use a mixed bullet format because... well... I'm lazy. This is by no means an exhaustive research project and I'm no expert, so this is just google-ish accurate info. Take it with a grain of salt and do your own research before straying from factory recommendations. Here we go.
- DOT numbers coincide with boiling points. The higher the number, the higher the boiling point.
- DOT 3, 4, & 5.1 are poly-glycol based and are compatible with one another, for the most part. We'll get back to that one in a minute.
- DOT 5 is silicone based and usually only used in specialized applications, like show cars. In case of a leak, it will not hurt paint.
- DO NOT ever mix DOT 5 with ANY other brake fluid. Period. Dot. No pun intended.
- Two different boiling points
- Dry equilibrium reflux boiling point (ERBP) – the boiling point of new, freshly opened brake fluid.
- Wet ERBP – the boiling point of brake fluid having absorbed 3.7 percent water.
For everyone other than racers who bleed/change their brake fluids after every race, the Wet boiling point is what is important. For those of us that do not change our fluid completely and often, it's always going to have some moisture in it.
From what I can tell, gen 4 Rams call for DOT 3. They say most DOT 4 fluids are compatible, but some have funky chemistry in them that make them incompatible. If it does not say expressly that it is compatible with DOT 3, do not use it. Same goes for DOT 5.1.
Viscosity also plays a part in this. Those who live north of the Mason Dixon may want to consider a lower viscosity fluid for obvious reasons.
- Specs for the two common beloved brands around here:
-- Red Line RL-600
--- Dry boiling point- 604F
--- Wet boiling point- 400F
--- Visc @ -40C- 1657 cSt
--- Visc @ 100C- 2.7 cSt
-- Amsoil DOT 3 & 4
--- Dry boiling point- 520F
--- Wet boiling point- 368F
--- Visc @ -40C- 817 cSt
--- Visc @ 100C- 2.0 cSt
-- Amsoil Dominator DOT 4 Racing
--- Dry boiling point- 580F
--- Wet boiling point- 410F
--- Visc @ -40C- 1550 cSt
--- Visc @ 100C- 2.0 cSt
Here is a comparison of 58 different brake fluids.
Bottom line: Pay attention to "WET Boiling Points". DO NOT ever use DOT 5. Consider a less viscous fluid if you live in a colder climate.
Get those turkey basters ready boys!
Okay, so I've spent the last couple hours [drinking beer and] researching the different types of brake fluids and what aspects are important to look at. I'm just going to use a mixed bullet format because... well... I'm lazy. This is by no means an exhaustive research project and I'm no expert, so this is just google-ish accurate info. Take it with a grain of salt and do your own research before straying from factory recommendations. Here we go.
- DOT numbers coincide with boiling points. The higher the number, the higher the boiling point.
- DOT 3, 4, & 5.1 are poly-glycol based and are compatible with one another, for the most part. We'll get back to that one in a minute.
- DOT 5 is silicone based and usually only used in specialized applications, like show cars. In case of a leak, it will not hurt paint.
- DO NOT ever mix DOT 5 with ANY other brake fluid. Period. Dot. No pun intended.
- Two different boiling points
- Dry equilibrium reflux boiling point (ERBP) – the boiling point of new, freshly opened brake fluid.
- Wet ERBP – the boiling point of brake fluid having absorbed 3.7 percent water.
For everyone other than racers who bleed/change their brake fluids after every race, the Wet boiling point is what is important. For those of us that do not change our fluid completely and often, it's always going to have some moisture in it.
From what I can tell, gen 4 Rams call for DOT 3. They say most DOT 4 fluids are compatible, but some have funky chemistry in them that make them incompatible. If it does not say expressly that it is compatible with DOT 3, do not use it. Same goes for DOT 5.1.
Viscosity also plays a part in this. Those who live north of the Mason Dixon may want to consider a lower viscosity fluid for obvious reasons.
- Specs for the two common beloved brands around here:
-- Red Line RL-600
--- Dry boiling point- 604F
--- Wet boiling point- 400F
--- Visc @ -40C- 1657 cSt
--- Visc @ 100C- 2.7 cSt
-- Amsoil DOT 3 & 4
--- Dry boiling point- 520F
--- Wet boiling point- 368F
--- Visc @ -40C- 817 cSt
--- Visc @ 100C- 2.0 cSt
-- Amsoil Dominator DOT 4 Racing
--- Dry boiling point- 580F
--- Wet boiling point- 410F
--- Visc @ -40C- 1550 cSt
--- Visc @ 100C- 2.0 cSt
Here is a comparison of 58 different brake fluids.
Bottom line: Pay attention to "WET Boiling Points". DO NOT ever use DOT 5. Consider a less viscous fluid if you live in a colder climate.
Get those turkey basters ready boys!
