5W-40 Oils
Our 5W-40 engine oils. Your handbook gives the grade and specification your engine needs.
QS 5W-40 MRV
A premium quality fully synthetic engine oil designed to provide outstanding performance and protection in modern petrol and diesel engines.
QS 5W-40 SP
A fully synthetic engine oil for use in gasoline vehicles.
What 5W-40 means
5W-40 is an SAE viscosity grade. The first number, followed by W for winter, shows how easily the oil flows when cold: the lower the number, the faster it reaches the engine at start-up. The second number shows how thick the oil stays at normal running temperature: the higher the number, the thicker the oil.
So a 5W-40 flows more easily from cold than a 10W-40, and is thinner when hot than a 5W-50.
Use a grade your car's manufacturer lists, with the specification it asks for as well: oils of the same grade can meet different specifications.
More in our guide to what the numbers on engine oil mean.