Mobil Pegasus™ 701 Series are premium natural gas engine oils formulated exclusively from specially selected base stocks of high stability. These lubricants provide the excellent performance and economy for a wide variety of engine types, service severity and fuel quality.

Mobil Pegasus 701 and 701 SAE 30 are formulated with ashless dispersants, effective oxidation and corrosion inhibitors, and antiwear agents. They provide excellent dispersancy, and good high-temperature stability. The formulation approach is very effective for controlling carbon and ash deposits in gas engines.

The ashless dispersants in Mobil Pegasus 701 and SAE 30 help prevent the formation of deposits that can cause detonation. Port carbon cleaning intervals in two-cycle, naturally aspirated and turbocharged gas engines may be extended by using Pegasus 701 Series oils. Mobil Pegasus 701 Series has increased engine overhaul periods and oil filter and spark plug life in both four-cycle and two-cycle gas engines.


Equipment lubricant recommendations

Data sheets

Features and Benefits

Mobil Pegasus 701 Series gas engine oils provide cleaner engines, long oil and filter life, and low lube oil consumption. The result is the potential for extended engine life and reduced overhaul costs.

Features Advantages and Potential Benefits
Good Anti-wear Properties Lower wear of engine components
Provides good break-in protection of high BMEP engines
Good Oxidation and Bulk Oil Stability Cleaner engines
Extended drain intervals
Reduced filter costs
Good resistance to oxidation and nitration
Reduces coking and formation of undercrown deposits
Good Corrosion Resistance Reduces valve guide wear in four-cycle gas engines
Protects bearings and internal components
Reduced port blockage, with longer intervals between cleaning
High Quality Basestocks Less power loss from detonation caused by combustion chamber deposits



  • Crankcases and power cylinders of spark-ignited two- and four-cycle gas engines
  • High speed two-cycle gas engines
  • Suitable for use in modern two-cycle and four-cycle slow-speed gas engines except where severity of application requires special heavy-duty, load-carrying performance
  • Highly loaded 4-cycle engines requiring anti-scuff protection
  • Reciprocating compressor cylinders compressing natural gas
  • High output or naturally aspirated turbocharged engines operating at or in excess of rated capacity under high temperatures


 Typical Properties


Mobil Pegasus 701 Series 701 701SAE 30
SAE Grade 40 30
Viscosity, ASTM D 445
cSt @ 40º C 132 85
cSt @ 100º C 13.5 10
Viscosity Index, ASTM D 2270 97 97
Sulfated Ash, wt%, ASTM D 874 <0.1 <0.1
TBN #, mg KOH/g, ASTM D 2896 2.2 1.7
Pour Point, ºC, ASTM D 97 -15 -18
Flash Point, ºC, ASTM D 92 249 238
Density @ 15º C, kg/L 0.885 0.881



Health and Safety

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