Mobil Delvac MX™ 15W-40 engine oil

Mobil Delvac MX™ 15W-40 is a high-performance mineral engine oil recommended for use in marine high-speed diesel engines, offering outstanding performance across all types of engines including modern, demanding low-emission diesel engines and existing diesel engines. Major engine builders have approved it.

Mobil Delvac MX 15W-40 oil offers potential operational benefits, including:

  • Reduction of sludge buildup and deposits for cleaner engines
  • Wear protection and viscosity control for longer component life
  • One engine oil for mixed-fleet operations
Related Product
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Product Information
Mobil Delvac MX™ 15W-40 performance profile
Technical resources
Guidelines for switchover to ExxonMobil marine lubricants
Learn about five different circumstances related to switching and mixing ExxonMobil marine lubricants.
Storage and handling: Best practices and guidelines for marine lubricants
Learn more about best practices for handling, storing and dispending ExxonMobil marine lubricants
Features and Benefits

High output, low emission diesel engines significantly increase the demands on engine lubricants. Tighter engine designs reduce oil consumption, resulting in less fresh oil make-up to replenish depleted additives. Top piston fire rings are located higher on the piston bringing the oil film closer to the combustion chamber where higher temperatures increase thermal stress on the lubricant. Increased fuel injector pressure and retarded timing improve fuel burn efficiency, but also increase engine temperatures and increase soot loads. Mobil Delvac MX 15W-40 is formulated from high performance base oils and a superior balanced additive system to provide optimum engine performance in modern diesel and gasoline engines as well as older models. The key benefits include:


Features Advantages and Potential Benefits
High thermal and oxidation stability Reduced sludge build-up, deposits and viscosity increase
TBN reserves Deposit control and acid neutralisation
Stay-in-grade shear stability Wear protection and viscosity control
Advanced detergency/dispersancy Cleaner engines and longer component life
Improved soot handling Improved viscosity control and used oil pumpability
Excellent low temperature properties Start-up wear protection
Component compatibility Longer gasket and seal life
Meets demanding specifications of key OEMs One engine oil for mixed fleet operations
Specifications and Approvals
Mobil Delvac MX 15W-40  

Recommended by ExxonMobil for use in:

  • Naturally aspirated and turbo-charged diesel powered equipment from leading Japanese, European, and American manufacturers
  • On-highway light and heavy-duty trucking
  • Off-highway industries including: construction, mining, quarrying, and agriculture
  • Mixed fleet applications
Typical Properties
Mobil Delvac MX 15W-40  
SAE Grade 15W40
Viscosity, ASTM D 445  
cSt @ 40ºC 117
cSt @ 100ºC 15.5
Viscosity Index, ASTM D 2270 140
Sulfated Ash, wt%, ASTM D 874 1.3
Total Base # , mg KOH/g, ASTM D 2896 12
Pour Point, ºC, ASTM D 97 -33
Flash Point, ºC, ASTM D 92 230
Density @ 15ºC kg/l, ASTM D 4052 0.88
Industry Sectors
  • Inland and coastal
Product Features
  • Enhanced Wear Protection
  • Extended Life
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