Mobilgard™ 12 Series diesel engine oil

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Product Information

   Mobilgard™ 12 Series A4-LR performance profile 637.454 KB/pdf
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Features and Benefits

Mobilgard 12 Series is formulated with base oils having proven successful performance in diesel engines. The additive system is balanced to provide excellent resistance to thermal degradation under moderately severe operating conditions. They also provide good engine cleanliness and superior wear protection.

When used as recommended, Mobilgard 12 Series oils provide the following features and potential benefits:

Advantages and Potential Benefits
Excellent thermal and oxidation stability Extended periods between inspections, overhaul and cleaning
Improved antiwear properties Reduced ring and liner wear
Excellent TBN reserve and retention Increased protection against corrosive wear
Excellent detergency/dispersancy properties Increased oil service life
Cleaner engines


The Mobilgard 12 Series diesel engine oils are intended for use as cylinder and bearing lubricants in marine and industrial diesel engines operating on distillate fuels or light fuel blends. They are particularly effective in high speed engines in fishing fleets; in new, severe service engines; and in many types of medium speed engines. They may be used as crankcase lubricants in large crosshead type diesel engines operating on high sulphur fuels.

Typical Properties

SAE Grade 30 40
Specific Gravity at 15ºC 0.896 0.899
Flash Point, ºC, ASTM D 92 266 272
Pour Point, ºC, ASTM D 97 -9 -9
Viscosity, ASTM D 445

cSt, at 40ºC 108 142
cSt, at 100ºC 12.0 14.5
Viscosity Index, ASTM D 2270 100 100
TBN, mg KOH/g, ASTM D 2896 15 15
Sulphated Ash, wt%, ASTM D 874 2.1 2.1
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