Castrol is here to serve every driver, every motorcyclist and every industry on earth. We do this through Liquid Enginering. That means creating high performance oils, lubricants, fluids and greases for every application you can imagine.
We also know that you need every part of your world to run smoothly, so we lubricate every part of the car or motorcycle you own, the escalators at your local shopping mall, the elevator at your office, and even the production line that made your refrigerator.
We are here for you in the world’s mines and quaries, its cruise ships and airliners, its wind farms and wheat fields. Whatever you need, we help make it happen.
When it's time for an oil change, knowing what engine oil to use is essential. The answer to that question gets more complex every day. The latest engines are getting smaller and more powerful all the time, and manufacturers are specifying complex full synthetic oils to cope with higher engine pressures and meet fuel efficiency targets.
If you're driving a muscle car or a European import, the manufacturer may well specify a full synthetic engine oil. Alternatively if you're driving an older domestic vehicle, the manufacturer may recommend a mineral oil. However, even though that's the most economical option, a full synthetic will almost certainly look after your engine better. Knowing what engine oil to use at every oil change is essential.
Your owner's manual will tell you which industry specification, type and grade of oil the manufacturer specifies, and we've also made it quick and easy to see all your options and make the right choice with our Oil Finder tool. Try it now.
Viscosity is a measurement of the thickness and lease of flow' in any liquid. For example, water is a thin liquid that flows freely, so we say that it has a low viscosity. Honey, on the other hand, is relatively thick and flows more slowly. So we describe honey as having a high viscosity. It's also worth noting that honey flows more easily - and is therefore less viscous - when it is slightly warm. Engine oil behaves in pretty much the same way, which is why mechanics will usually run an engine for a minute or two before draining used engine oil away to replace it.
There are so many engine oils out there, which one is right for your vehicle? Well, there are three basic types: mineral, part synthetic and full synthetic. Mineral oils are the least refined of the three, which means they cost less, but also provide less protection, performance and economy than the other options. Part synthetic engine oils are a blend of mineral oil and synthetic oil, to give added performance, but still at a lower cost than full synthetic engine oils. Full synthetics are the most expensive engine oils as they are highly refined, but offer the best and protection and economy to absolutely every vehicle.