Piston assembly

Mobil SHC Pegasus

Synthetic Gas Engine Oil

Our Mobil SHC Pegasus™ Series gas engine oils provide maximum protection for high-output, low-emission four-cycle gas engines while also helping to increase fuel efficiency and reduce CO2 emissions. They are formulated for heavily loaded valve train components, pistons, liners, bearings and gear trains.

Proven to increase efficiency up to 1.5 percent*, these lubricants can also:

  • Reduce the formation of carbon and varnish deposits
  • Minimize oil consumption
  • Maintain engine cleanliness during extended drain intervals
  • Lower operating and maintenance costs
  • gauge

    Formulated to potentially help limit fuel consumption

  • gears

    Promotes engine efficiency and reliability by helping control deposits in combustion chamber and piston ring zone

  • fuel efficiency

    Up to 1.5% increase in fuel efficiency compared to standard natural gas engine oils*

  • runtime

    Helps maximize engine availability through long drain intervals — more than 50,000 hours documented

Equipment lubricant recommendations

Our Mobil Serv℠ Product Selector tool will help you identify lubricant(s) for your specific equipment.

Data sheets

Product information

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Features and Benefits


Advantages and Potential Benefits

Outstanding anti-wear characteristics

Help to protect heavily loaded valve train components, pistons, liners, bearings, and gear trains

Excellent detergent-dispersant system

Controls the formation of carbon and varnish deposits to minimize oil consumption and maintain engine cleanliness even during extend drain intervals

Exceptional oxidation stability, nitration resistance and thermal stability

Provides the opportunity to extend drain intervals by four to eight times that of conventional gas engine oils

Low volatility

Reduces oil consumption and reduces deposit formation



Turbocharged, naturally aspirated, medium to high speed four-cycle engines requiring a low ash oil

Lean-burn and stoichiometric four-cycle engines operating under high load, high temperature conditions

High-speed four-cycle gas engines used in cogeneration applications

Natural gas fuelled engines equipped with catalytic converters

Gas engines operating on fuel that contains low levels of H2S


Specifications and Approvals

This product has the following approvals:

INNIO Waukesha Engine APG 1000 Applications Using Commercial Quality Natural Gas


Properties and Specifications




SAE 30

Density @ 15.6 C, g/cm3, ASTM D4052


Ash, Sulfated, mass%, ASTM D874


Flash Point, Cleveland Open Cup, °C, ASTM D92


Total Base Number, mgKOH/g, ASTM D2896


Viscosity Index, ASTM D2270


Kinematic Viscosity @ 100 C, mm2/s, ASTM D445


Pour Point, °C, ASTM D97


Kinematic Viscosity @ 40 C, mm2/s, ASTM D445



Health and safety

Health and Safety recommendations for this product can be found on the Material Safety Data Sheet (MSDS) @ http://www.msds.exxonmobil.com/psims/psims.aspx

  • Energy efficient
  • Enhanced wear protection
  • Extended life
  • Keep clean
  • Severe operating conditions
  • Gas engine oils - by sulfated ash
  • Gas engine oils - by OEM

Technical resources

All Mobil SHC Pegasus resources