Mobilgard™ M440 — 40 BN Medium-Speed Trunk Piston Engine Oil | Residual Fuel

40 BN

TBN mgKOH/g

SAE 40

Grade

Residual

HFO — High S

DAC

Patented Test

242°C

Flash Point

Medium

Speed Trunk Piston

40 BN — Maximum Acid Neutralisation

Highest TBN in the M-Series — 40 mgKOH/g provides maximum acid neutralisation capacity for engines burning higher-sulphur residual fuels or operating under the most severe conditions where 30 BN M430 may be insufficient.

Outstanding Residual Fuel Compatibility

High performance additive detergent technology provides outstanding fuel-lube compatibility — reducing sludge formation and enabling longer oil life and cleaner engines in the most severe HFO-fuelled medium-speed applications.

Excellent Engine Cleanliness

Reduced deposits in piston undercrown and ring belt areas, with advanced detergency and dispersancy keeping camshaft and crankcase spaces clean — supporting extended overhaul intervals in the harshest residual-fuelled medium-speed marine engine applications.

Improved Anti-Wear Protection

Improved anti-wear properties extend the life of critical wear surfaces, while outstanding rust and corrosion protection guards against water and acidic corrosion in demanding operating conditions.

ExxonMobil Patented DAC Test

Developed using the patented DAC (Detecting Asphaltene Contamination) test — detecting asphaltene contamination that could cause piston damage and excessive oil consumption if undetected in high-sulphur fuel operation.

High Performance Thermal Stability

Excellent TBN retention and resistance to viscosity increases over long operating periods, with low volatility base stocks that help minimise lubricant consumption — maintaining consistent protection throughout extended drain intervals.

High-Sulphur HFO Operations

Medium-speed engines operating on higher-sulphur residual fuels — where the 40 BN provides greater acid neutralisation capacity than the 30 BN M430 for more aggressive sulphuric acid neutralisation requirements.

Most Severe Residual Fuel Applications

Main propulsion and auxiliary engines on deep-sea vessels, main propulsion engines on coastal and river ships, and stationary power plants — where maximum TBN and cleanliness performance is required.

Low Crankcase Oil Consumption Engines

Especially beneficial in engines with low crankcase oil consumption or operating with low cylinder liner temperatures, where relatively high alkalinity reserves provide superior protection against acids that access the crankcase.