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Frequently asked questions

Find answers to common questions about our products and services

  • The "668" refers to the ISO VG 668 viscosity grade, a high-viscosity classification typically used in heavy-duty industrial transmission and gearbox applications that require thick, high-load protection. This grade is generally not suitable for standard automotive transmissions, which use much lower-viscosity fluids.

  • Synthetic base stocks generally provide superior oxidation resistance, greater thermal stability across a wider operating temperature range, and longer service life compared to conventional mineral-based equivalents at the same ISO VG grade.

  • This pail contains 5 gallons (approximately 18.9 liters) of fluid. Whether that is sufficient for a full fill depends on your specific equipment's sump capacity, so always check the OEM manual for the required volume before ordering.

Key Features

  • ISO VG 668 high-viscosity grade formulated for heavy-duty industrial transmission and gearbox applications that require thick, high-load protection.

  • Synthetic base stocks deliver superior oxidation resistance compared to conventional mineral-based equivalents at the same ISO VG grade.

  • Greater thermal stability across a wider operating temperature range than conventional mineral-based transmission fluids.

  • Longer service life than conventional mineral-based equivalents at the same viscosity grade, reducing fluid change frequency.

  • Each pail contains 5 gallons (approximately 18.9 liters) of fluid — check your equipment's OEM manual to confirm required sump capacity before ordering.