Brake Fluid Comparisons

DOT 4 Min Standard

Torque RT700™

Castrol SRF

Endless RF-650

Motul RBF600*

Motul RBF660*

Dry Boiling Point (°F)
(as per lab testing)

685 °F

616 °F

616 °F

570 °F

588 °F

Wet Boiling Point (°F)
(as per mfr’s specs)

311 °F

439 °F

517 °F

424 °F

420 °F

400 °F

Wet Boiling Point (°F)
(as per lab testing)

438 °F

536 °F

412 °F

398 °F

400 °F

High Temperature Stability
(Boiling Point Change)

 ±5.4 + 1 ° that original BP exceeds 437 °F

-1 °F

-3.5 °F

-3.5 °F

-7.2 °F

-3.5 °F

Chemical Stability
(Boiling Point Change)

 ±5.4 + 1 ° that original BP exceeds 437 °F

-1.23 °F

-3.6 °F

-3 °F

-2 °F

-3 °F

Vapor Pressure

<0.01 mmHg @ 68 °F

N/A

N/A

N/A

N/A

Density (Specific Gravity)

1.095

N/A

N/A

N/A

pH
(7 = Neutral)

7.0 - 11.5

7.3

9.1

5.7

7.1

6.8

Viscosity -40 °F (cSt)

1800 max

1501

1202

2543

1660

1434

Viscosity 212 °F (cSt)

1.5 min

2.1

3.5

3.5

2.7

2.7

Compressibility

No standard

 5.19E-05 @ 212 °F @ 5800 psi (400 bar)

  6.487E-05 @ 212 °F @ 5800 psi (400 bar)

  5.868E-05 @ 212 °F @ 5800 psi (400 bar)

N/A

N/A

(Numerically lower numbers denote lessor compressibility)

 3.969E-05 @ 122 °F @ 5800 psi (400 bar)

  5.230E-05 @ 122 °F @ 5800 psi (400 bar)

  4.884E-05 @ 122 °F @ 5800 psi (400 bar)

N/A

N/A

  3.405E-05 @ 68 °F @ 5800 psi (400 bar)

  4.621E-05 @ 68 °F @ 5800 psi (400 bar)

  4.846E-05 @ 68 °F @ 5800 psi (400 bar)

N/A

N/A

Reserve Alkalinity

No standard

84

10

5

33

36

 % H2O Content at Testing

No standard

0.01

0.01

0.15

0.19

0.22