Product Description

Mobilgard 525 is a marine diesel engine cylinder oil for crosshead engines running low and ultra low sulphur distillate fuels and meets the requirements of MAN and Wartsila engines. Designed to protect in extreme environments, Mobilgard 525 has an optimum viscosity of 20 cSt at 100ºC and low volatility to ensure lubricant distribution and oil film retention and help protect engine parts.


•  Combats the deposits and scuffing related engine wear associated wth low sulphur fuels

•  Excellent thermal and oxidative stability to ensure performance in a variety of engine conditions

•  Formulated with detergent technology required to deliver excellent performance with low-sulphur fuel

•  Detergency system provides strong control of piston groove deposits which is a critical area for distillate fuel operation

•  Marine crosshead engines designed for increased power and fuel efficiency

•  Earlier engine designs and engines in slow speed steaming operation

Specifications and Approvals

This product has the following builder approvals:
MAN B&W 2-Stroke Diesel Engines
WARTSILA & Sulzer 2-Stroke Engines <0.5% max. Sulfur Distillate Fuel

Properties and Specifications

Grade SAE 50
Flash Point, °C, ASTM D92 286
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445 20
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445 226
Pour Point, °C, ASTM D97 -9
Specific Gravity, 15 C/15 C, ASTM D4052 0.909
Total Base Number, mgKOH/g, ASTM D2896 25
Viscosity Index, ASTM D2270 102

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.