1. HOME
  2. PRODUCTS
  3. OUR BRANDS
  4. VISCOSITY GRADES
  5. 10W-40

10W-40 Engine Oil Grade

Castrol’s 10W-40 engine oil can endure a wide range of temperatures. Optimise your performance and ensure your vehicle runs smoothly. Learn more here.

10W-40 Engine Oil Grade

10W-40 engine oil

 

10W-40 engine oil is extremely adaptable, handling a wide range of temperatures and maintaining its efficacy both in low winter temperatures and when operating in hotter environments.

 

What does 10W-40 mean?

 

This short video will tell you all you need to know about 10W – 40 engine oil.

Loading

To view this content, go to the cookie preferences page, linked in the footer, and switch on advertising and campaign cookies.

'This video has been optimised for iOS 14 and above. For the best experience, please update your software.'

10W – 40 is used to describe the oil’s thickness. “W” stands for winter. The number before the “W” signifies the viscosity of an oil at low temperatures – for example before you start your engine. The number following the “W” indicates its viscosity at normal operating temperatures when the engine is running. All engine oils have a resistance to flow and all resistance levels have been assigned a number. The 10 number indicates that the oil is thin at low temperatures and better able to operate in cold start and icy conditions. 

 

castrol 10W-40 product range


Castrol MAGNATEC offers fully synthetic engine oil and semi synthetic engine oil within its 10W – 40 range. 


Working in conjunction with leading universities, Castrol has engineered MAGNATEC with DUALOCK technology  to provide protection during modern driving in heavy traffic conditions with frequent stops and starts. MAGNATEC’s molecules cling to critical engine parts and lock together to protect the engine against warm-up wear and stop-start wear.


Castrol GTX  10W – 40 engine oil is fully synthetic. It breaks down sludge and protects against the formation of future sludge.