Mobilgard™ 540 AC

ExxonMobil marine , Canada

High Performance Marine Diesel Engine Cylinder Oil

Product Description

Mobilgard™ 540 AC by ExxonMobil is an MAN ES Category II approved, premium quality, high-performance marine diesel engine cylinder oil designed to effectively lubricate and deliver advanced cleanliness through effective deposit control across wide-ranging fuel and engine conditions.


Through the use of advanced formulation and detergency technologies in conjunction with a low Base Number (BN), Mobilgard 540 AC has demonstrated the ability to deliver advanced cleanliness and wear protection, whilst optimising cylinder oil feed-rates and effectively managing acid neutralisation in a range of engines and fuel applications.


Mobilgard 540 AC has been granted Category II status by MAN Energy Solutions. Its formulation has been designed for optimal lubrication at the elevated peak firing pressures and liner temperatures found in modern marine two stroke engines. The use of this product, in combination with the Mobil Serv℠  Cylinder Condition Monitoring onboard monitoring, will help operators to achieve the best possible cylinder oil feed rates, while maintaining excellent lubrication.


This Category II cylinder oil is applicable for use in all MAN B and W two - stroke engines across LNG, Distillate and Very Low Sulphur Fuel Oil (VLSFOs) operation and recommended for engines Mark 9 and higher.


Features and Benefits

Mobilgard 540 AC combines the use of high-quality, globally consistent base stocks with a superb additive formulation to provide superior detergency capability, which can lead to cleaner engine components.


Mobilgard 540 AC also offers outstanding resistance to oxidation, acid formation and excellent deposit control due to increased temperatures and pressures within combustion cylinders, which are particularly prevalent in LNG fuel operation.



Mobilgard 540 AC is formulated to provide outstanding performance in marine crosshead engines operating on a wide variety of fuel applications, including continuous LNG use.


This Category II cylinder oil is applicable for all engines and recommended for MAN B&W two-stroke engines Mark 9 and higher.


Specifications and Approvals


This product has the following approvals:

MAN Energy Solutions Copenhagen (Heritage MAN B&W) Category II for 2-Stroke Marine Engines


Properties and Specifications




SAE 50

Viscosity Index, ASTM D2270


Total Base Number, mgKOH/g, ASTM D2896


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


Pour Point, °C, ASTM D97


Flash Point, Pensky-Martens Closed Cup, °C, ASTM D93


Density @ 15.6 C, kg/m3, ASTM D4052


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) @

All trademarks used herein are trademarks or registered trademarks of Exxon Mobil Corporation or one of its subsidiaries unless indicated otherwise.


Imperial Oil 

Petroleum and Chemicals Division
Lubricants and Specialties
240 Fourth Ave SW
C. P. 2480, Station M
Calgary AB T2P 3 M 9



Typical Properties are typical of those obtained with normal production tolerance and do not constitute a specification. Variations that do not affect product performance are to be expected during normal manufacture and at different blending locations. The information contained herein is subject to change without notice. All products may not be available locally. For more information, contact your local ExxonMobil contact or visit
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