Gas Engine Oil

Mobil Pegasus™ 605 Ultra 40 is the latest generation of gas engine oil primarily intended for the lubrication of modern medium and high-speed four-cycle engines operating on landfill gas that contains contaminants such as hydrogen sulphide, halides or siloxane. Its formulation has been carefully balanced to provide extended oil drain intervals, control the formation of carbon and varnish deposits, with very good anti-wear and anti-scuff performance.

Features and Benefits

• Exceptional oxidation stability, nitration resistance and thermal stability that help extend oil life, clean engines, reduce filter costs and resist deposit formation

• Very good anti-wear characteristics help to reduce wear of engine components, reduce scuffing of liners in highly loaded gas engines and provide break-in protection

• Extraordinary detergent-dispersant system provides protection of upper cylinder and valve train components, clean engines and long filter life

• Optimized TBN and reserve alkalinity help protect valve seats and faces on four-cycle engines, improve spark plug performance, and reduce power loss from detonation


• Engines operating on fuel containing corrosive materials such as THCl (Total Organic Halides as Chloride) such as landfill or biomass gas

• Gas engines operating on fuel that contains moderate levels of hydrogen sulfide (H2S)

• Spark ignited four-cycle gas engines with very low lube oil consumption

• Medium and high speed four-cycle engines equipped with catalytic converters requiring a low ash gas engine oil

• Reciprocating compressors operating on natural gas that contains sulphur or chlorine compounds

Specifications and Approvals

This product has the following approvals:
GE Waukesha Engine Landfill Gas Applications
MWM GmbH TR 0199-99-2105
INNIO JENBACHER TI 1000-1109 (Class B fuel gas, Series 2 & 3)
INNIO JENBACHER TI 1000-1109 (Class B fuel gas, Series 4A, 4B & 4C)
INNIO JENBACHER TI 1000-1109 (Class B fuel gas, Series 6 up to version E)
INNIO JENBACHER TI 1000-1109 (Class C fuel gas, Series 2 & 3)
INNIO JENBACHER TI 1000-1109 (Class C fuel gas, Series 4A & 4B)
INNIO JENBACHER TI 1000-1109 (Class C fuel gas, Series 6 up to version E)
Caterpillar Energy Solutions TR 2105, Lube Oils for Gas Engines (CG132, CG170, CG260)
MAN M 3271-4
INNIO JENBACHER TI 1000-1109 (CAT (catalyst) approved)
This product meets or exceeds the requirements of:

Properties and Specifications

Grade SAE 40
Ash, Sulfated, mass%, ASTM D874 0.6
Density @ 15.6 C, kg/l, ASTM D1298 0.85
Flash Point, Cleveland Open Cup, °C, ASTM D92 268
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445 15
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445 137.5
Pour Point, °C, ASTM D97 -21
Total Base Number, mgKOH/g, ASTM D2896 5.3
Viscosity Index, ASTM D2270 110

Health and safety

Health and Safety recommendations for this product can be found on the Material Safety Data Sheet (MSDS) @


It cannot be guaranteed that the product information given above is up to date. For the latest version of the Product Data Sheet we refer to the product library of ExxonMobil.