Shell Argina S4 40
Shell Argina S4 40 is a multifunctional crankcase lubricant developed for highly rated medium-speed trunk piston diesel engines operating on residual fuel oils. With a Base Number (BN) of 40 and SAE 40 viscosity grade, it is specifically designed for conditions of high oil stress and has been optimised to improve deposit control and long-term engine cleanliness.
A key benefit of Shell Argina S4 40 is extended oil life. The BN40 formulation has been engineered to resist oxidation and maintain alkalinity over extended operating periods, helping to reduce the amount of oil sweetening required. By preserving BN retention under severe operating conditions, the oil supports improved cost control and operational efficiency.
Shell Argina S4 40 delivers enhanced engine protection through a high level of detergency, promoting exceptionally clean crankcases, valve decks and pistons. The formulation has been further optimised to reduce deposits in critical areas such as piston undercrowns, helping to control wear and maintain reliable engine performance under high load conditions.
System efficiency is supported by a high detergency and low dispersancy balance, allowing effective release of contaminants and water in centrifugal separators. This contributes to improved oil cleanliness and separator performance. Shell Argina S4 40 can also be used to top up engines operating on other members of the Argina family, enabling immediate BN control without the need for a complete oil change.
The oil is recommended for medium-speed industrial or marine propulsion and auxiliary engines burning residual fuels under high oil stress conditions. These conditions typically occur in newer engine designs (less than 10 years old and/or fitted with flame rings), where oil consumption is between 0.5 and 1 g/kWh, load factors exceed 85%, and fuels with sulphur content greater than 2% are in use. Shell Argina S4 40 may also be used in marine engine reduction gears and certain other shipboard applications where specialist lubricants are not required.
Shell Argina S4 40 is approved by Wärtsilä and MAN Energy Solutions. Typical physical characteristics include SAE 40 viscosity grade, kinematic viscosity of 13.7 mm²/s at 100°C, viscosity index of 104, density of 916 kg/m³ at 15°C, flash point of 230°C, pour point of –9°C, BN of 40 mg KOH/g and sulphated ash content of 5.0%. It also demonstrates strong load carrying performance in FZG gear testing (failure load stage 11).
