It is difficult to overstate the importance of oil in car operation. Just like it is impossible to overstate the importance of blood in human bodies. But while living organisms can ‘refresh’ their blood, the mechanical contraptions require oil changes at certain intervals. To complicate matters further, there are several types of “machine blood” for different components, each having its own service life.
But in general, these are the purposes of those service fluids (aka oils) in your vehicle:
As your car works, engine oil is subjected to extreme heat, pressure and acidic gases. So, it wears down. This is called oil degradation. One of the surest symptoms of it is when your oil level warning suddenly lights asking for a top-up.
The next step would be the so called ‘carbon build-up’. It is when oil turns into gooey sludge that quickly clogs all passages that supply oil to the engine internals. Unfortunately, there is no warning lamp in the dash for it. There is a lamp for low oil pressure, but in most cases, you see it when it is too late.
So, to keep things up to snuff, how often do you change the oil? This is a sensitive topic that requires a bit of a history lesson first.
In the old days (up to early 1980s) most oils had few additives and did not last long, hence the replacement intervals of around 5,000 kms (or 3,000 miles for those down South). But those oils were cheap, and the replacement procedure was super-simple and quick. Even a school drop-out at a corner gas station or some ‘instant lube’ place staff could fathom it without breaking something.
In the late 1980s oil makers introduced the so-called ‘synthetic’ oils. These tend to last quite a bit longer but were expensive. Common recommended intervals reached 10,000 kms (or 6,000 miles). Still, for vehicles with turbochargers that became popular around the same time, the shorter regimen (5-7 thousand kms) remained.
In the 2000-2010’s, cars became more complicated. An ‘oil change’ became more involved and more expensive, sometimes requiring partial disassembly and special tools, or even hooking up a computer to the serviced vehicle.
And roughly at the same time to attract more sales car makers rolled out “oil changes for free” during lease or finance period. That interestingly coincided with ever-increasing recommended oil change intervals, which eventually reached 20,000 kms, or more.
Yet the engine oil has not changed much in the past 30+ years – if you forego marketing blurb and go straight to chemical composition and properties, the stuff you pulled off the shelf at NAPA in 1992 and in 2022 is pretty much the same.
What has changed though, is the engines. To meet ever-stricter emissions and fuel consumption requirements, car power trains carry lots of technology that puts enormous additional stress on the engines – and engine oil. Turbocharging, elevated operating temperatures, high-pressure cooling systems, direct injection and much more.
So, here’s a bit of simple non-solicited advice. If you want your car to be happy and stay happy for a long time, follow a simple plan: