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Vehicle's Hydraulic Braking System

  1. Sep 2, 2015 #1

    In Vehicle Braking system manufacture suggest me to use SAE 20W-40/APIGL 4/ZFTF - ML05F oil for disk brake. But i want to use ISO VG 46. So is it feasible oil?
  2. jcsd
  3. Sep 2, 2015 #2


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    You should contact the manufacturer of the vehicle, and of the oil.
  4. Sep 2, 2015 #3
    Why do you want to use an oil not approved by the manufacturer?
  5. Sep 2, 2015 #4
    Actually in this type machine other manufacturers are using same oil which use in Hydraulic ISO VG 46 for braking system. But in our machine manufacturers suggest different. So i want to know what problem is create after using other oil.
  6. Sep 3, 2015 #5


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    Is it an internal wet disk brake system ?

    Using the wrong oil can result in failure of rubber seals or friction material. The oil can have different moisture control mechanisms which may cause corrosion. A different oil can denature at a different temperature.

    Brakes are too important to risk failure, follow manufacturers specifications. Contact the manufacturer.
    Ask the manufacturer why they specify one particular type of oil.
  7. Sep 3, 2015 #6
    Yes its internal wet disk brake system.

    If i use same oil which recommended by manufacturers then i have to attached separate cooling system for it. To avoid this problem and extra system i want to use same oil.
  8. Sep 3, 2015 #7


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    Does the vehicle already have a hydraulic system running ISO VG 46 that is filtered and cooled ?
    Is that the oil you want to use for the brakes?

    What happens if a hose blows and the hydraulic oil is then not available?
    How will you guarantee fluid supply to brakes when other systems take all available fluid resulting in low fluid supply pressure?
    Running wet clutches and brakes without hydraulic oil destroys the friction material immediately and requires a rebuild.

    Maybe the manufacturers recommended oil has safer and longer lasting lubricant properties than ISO VG 46.
    Also, because it is in a separate system, it is less likely to run the brakes dry following a general hydraulic fluid failure.
  9. Sep 3, 2015 #8
    Yes Vehicle already running with ISO VG 46. And its have separate cooling and filtering System.

    For Braking I have taken connection from steering system. And steering system are set on priority, So no failure of fluid. Also i have fitted accumulator for emergency supply.
    And service brake working pressure is 60 Bar and all other system are 100 Up.
  10. Sep 3, 2015 #9


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    That does seems like a reasonable solution.
    I would still ask the manufacturer why they specify the oil they do and what will happen if you use ISO VG 46.
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