We can probably all recall the Castrol advertising campaign “Oils Ain’t Oils” with Sol and his gangster friends – designed to introduce the motorist to ‘man made’ synthetic oils.

But what’s the difference, what’s the best and what should YOU use?

Synthetic Versus Natural – what’s best?

Initially developed in pre war Germany in an attempt to lessen their dependence on the natural stuff from the ground, it wasn’t until the early seventies that synthetic oil really got underway and became a universally accepted as a proper substitute.  Depending on the brand, the actual make up of synthetic oils can vary condiderably. Some brands even use very highly refined crude oil in their formula, others don’t.  Some use ethanol, a derivative from natural gas, and others use various chemicals in a laboratory controlled formula rather than the natural product that comes out of the ground.

Advantages of Synthetic Oil
Much better stability in its chemical make up, more uniform with much less impurity.
Much less evaporative loss.
Does the job of lubricating much better at both low and high temperatures
Cleans the engine much better, removes sludge and is more resistant to oxidization.
Lasts much longer than natural engine oil. Its service intervals for an oil change can be doubled or even tripled against the real thing.
Because it eliminates sludge build up and develops a cleaner engine environment it should show some improvements in fuel economy due to more efficient running and reduced friction.

So Why Think Twice?

As you can see there are some really compelling advantages with Synthetic oil, but there is one drawback – price!

Synthetic oil is much more expensive, up to double the cost and sometimes even more, and, in some circumstances, may not be worth it.
If you plan to change your car frequently then the extra cost is difficult to justify.
Similarly if you change your oil frequently then conventional oil will suffice.
But if you take advantage of synthetic oils’ longer life you’ll find it won’t cost you more and it will give you a cleaner motor.

A Word Of Caution

When deciding which is best you need to consider the age of your car.
If you have an older vehicle and you switch from mineral oil to synthetic you may find that oil leaks occur due to the better viscosity and efficiency of the synthetic stuff.
Otherwise if you have a modern car it should be quite safe to switch.
Or as another option you can always choose a semi-synthetic oil, which is cheaper and many motor mechanics see it as the best of both worlds, or maybe just the convenient compromise.