Oil. Black gold. Texas tea.
It’s crazy to think about, with classic and specialty marques cornering the market on 20W50 engine oil, but 0W8 engine oil is now on the shelves!
I know, I know, why not just use water, right!?
Toyota in particular has been using 0W16 and 0W8 for the last couple of years in a bunch of different vehicles - “Specially designed for hybrid vehicles”, 0W8 is marketed as a “fuel economy” oil. Many, (including myself) have raised at least one hairy eyebrow to the thought of sending such a lightweight into the ring, so let’s have a closer look, scratch the surface and maybe learn something new, (putting pitchfork down).
First of all, machining and manufacturing techniques are better than they have ever been. The consistency with which new engine parts are produced nowadays is incredible - not just consistency regarding quality control, but also with critical tolerances.
In the “good ol’ days” it may have been okay for wrist pin bushings or piston ring gaps to be within a thousandth of an inch of each other - no bueno today.
These new techniques mean that new engines have stronger AND lighter internal parts requiring smaller oil passages and tighter clearances between bearing surfaces and more efficient oil and coolant pumps - this means that less overall material will be used, creating less mass and weight…but with equal or BETTER power output.
Remember the engines of the 1970’s? How is it possible that Ford could produce a 7.5 liter engine that only produced 320 horsepower!? Jaguar’s modern P300 3.0 liter engine makes 380 horsepower, (albeit supercharged, but still…).
On one hand, I still think that 0W8 is ridiculous.
We demand SO much from our engine oil beyond just lubrication: break down and suspend carbon and particulate, tolerate extreme temperature swings, assist with cooling, work with emissions equipment…wait, what was that last one?
That’s right folks, the engine oil that you use has an effect on your vehicles emissions systems.
It is very important that the oil is compatible with your vehicle.
All engines will use or “consume” a little bit of oil. Cylinder walls are finished with a “cross hatch” pattern that are designed to hold a film of oil that assists in both lubrication on the piston and sealing of the piston rings.
A little bit of this film will naturally make its way into the combustion chamber and be burnt.
Oil vapour is also recirculated into the intake manifold on all engines post 1964. Finally, many new engines use turbochargers and superchargers which will naturally consume a little bit of oil in normal operation, (BMW allows up to 1 Liter/1000kms).
Any oil entering the exhaust will meet the catalytic converter and non-approved oils can react badly and shorten its lifespan.
Engine oils are a mixture of as many as 14 different elements and chemicals. The wrong mixture can react negatively if not approved for the application.
A good example of this is the use of zinc; Most older engines relied on zinc, (ZDDP) in the engine oil as a friction reducing additive.
ZDDP reacts to the elements in catalytic converters and breaks them down, damaging the catalyst and rendering it ineffective - so modern oils practically eliminated ZDDP, but if we use these modern oils in an older engine, we can hurt the camshaft and valvetrain. Sigh.
“But, Kevin”, you say, “why don’t you just put in a ZDDP additive?”. Same consideration as above: Oils are chemical mixtures. Depending on the oil, additives may have a negative or unintended effect because the additive is itself, a chemical mixture. Too much ZDDP causes the engine oil to become acidic and bibbitybobbityboo, you’ve toasted your bottom end bearings.
This is such a huge topic to cover - there is the conventional vs synthetic argument, diesel oils, high mileage oils, break-in oils for freshly built engines, etc… but short story: Engineers are not dumb. Read the labels and choose an engine oil that is designed for your application and that meets the engine’s specifications….even if it’s 0W8.
If you found this interesting, or if you want to go for a deep dive into oil science, (and conspiracies), I highly recommend checking out @themotoroilgeek on youtube and beyond.
Commentaires