Castrol RLX Super 40
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Monograde diesel engine lubricant


Castrol RLX Super 40 is a 5th Generation (LMOA) zinc and chlorine free engine crankcase lubricant which has been specifically designed for the lubrication of diesel propulsion, diesel electric and stationary power generation installations where a zinc-free lubricant is specified.


Castrol RLX Super 40 is formulated to meet the requirements of engines manufactured by General Motors Electromotive Division (GM-EMD), General Electric (GE) and ALCO. This grade is suitable for all engines fitted with silver bearings, particularly those used in Marine and Offshore power generation sets.

  • Optimum balance of detergency and dispersancy reduces ring sticking and engine deposits, resulting in cleaner engines that maximize operating performance. With extended oil drain intervals, engine downtime is further reduced.
  • Selected additive system provides excellent protection against wear and acid corrosion resulting in increased engine component life.
  • Exceeds detergency requirements of API CF and CF-2.
  • High viscosity index base oil allows control of oil consumption and maintains excellent oil film between bearings at high operating temperatures.
  • Castrol RLX Super 40 is fully compatible with other 5th generation (LMOA) lubricants.
Name Method Units RLX Super 40
Density @ 15°C


ASTM D1298 g/ml 0.890
Kinematic Viscosity @ 100°C


ASTM D445 mm²/s 14.5
Viscosity Index


ASTM D2270 100
SAE Number


Total Base Number, TBN


ASTM D2896 mg KOH/g 13.7
Pour Point


ASTM D97 °C -15
Flash Point (PMC)


ASTM D92 °C >200
Sulphated Ash


ASTM D874 % m 1.5
Zinc Content


ppm <10
Chlorine Content ppm <10

Conforms to the requirements of `Generation 5` for GM-EMD and `Generation 4LL` for GE. Meets the oil recommendations for Caterpillar 3600 series engines. Suitable for all ALCO engines


All packages should be stored under cover. Where outside storage is unavoidable drums should be laid horizontally to avoid the possible ingress of water and the obliteration of drum markings. Products should not be stored above 60C, exposed to hot sun or freezing conditions.

Avoid prolonged or repeated contact with skin. Wash thoroughly after handling

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