And what did we buy today?

Castrol Magnatec Stop-Start 10w-30 engine oil for my Ford Falcon AU2. Normally $47, I paid $13.00 (was on special for $22 + I had $9 membership credit = $13).

Engine can accept anything from 10w30 to 10w50 but the manual recommends that "for best fuel economy use 10w30"

I love how the oem specified engine oil is 10wxx in Australia and many other places. In the US, the manufacturers have been convinced to spec 0wxx oils with the assumption of better economy. This was done by the epa or some other well meaning organization. The benefits are microscopic if at all measurable.
That’s how I find out what my car really should be using.
 
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I use 0-20 grade (as recommended by the manufacturer) but I've also had doubts on how this thin oil might contribute to wear in the long term. I've owned the car from new and now find I need to add around a litre and a half per year at just 50K mileage.

I asked the dealer about whether using 5-30 or 10-40 would make sense and the answer was a definite no. The handbook actually says that all these and also 20-50 is 'acceptable' and then adds the disclaimer that although 0-20 is the preferred range, it may not be suitable for continuous high speed driving (or words to that effect).

Have you tried putting 0-20 in a freezer ? Its still like treacle.

YouTube
 
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I love how the oem specified engine oil is 10wxx in Australia and many other places. In the US, the manufacturers have been convinced to spec 0wxx oils with the assumption of better economy. This was done by the epa or some other well meaning organization. The benefits are microscopic if at all measurable.
That’s how I find out what my car really should be using.

Take this as advice, not definitive information. This is information that I've gleaned over by reading online. I'm not an expert in the field.

Actually 0w-xx is used in cold climate regions to prevent the oil from solidifying. Its a regional thing, in Australia it doesn't get cold enough to use 0w-xx.

The first number is the weight rating at atmospheric temperature. (when the engine is off)
The second number is the weight rating of the engine oil as it warms up to operating temperature.

Engine oil thickness is like a bell curve, it gets thicker below atmospheric temperatures (below 0 deg centigrade) and it also gets thicker above atmospheric temperatures (at engine operating temperatures).

Motor oil - Wikipedia

The SAE designation for multi-grade oils includes two viscosity grades; for example, 10W-30 designates a common multi-grade oil. The first number '10W' is the equivalent grade of the single grade oil that has the oil's viscosity at cold temperature and the second number is the grade of the equivalent single-grade oil that describes its viscosity at 100 °C (212 °F). Note that both numbers are grades and not viscosity values.
At atmospheric temperatures which are below engine operating conditions the engine oil runs like water, which is why I always do my engine oil changes just after turning the engine off after I've run it around the block just once. So the oil is still warm/hot but it is not at operating temperature.

So the first weight rating is used to allow the oil to get to where it needs to be quicker in all atmospheric conditions, both winter and summer, at least that is the case for most of Australian regions. The quicker the oil flows through the engine the better it will protect the engine (75% of engine wear occurs during initial startup). But once it is at 100 deg c it thickens up so that it can provide protection to the engine.

So if I were to use 0w in my car here in Australia I would have to be in the deep south (close to the south pole, on the southern tip of Tasmania) to justify using it.

There is no fuel economy benefits to changing the first figure because its the second figure which improves fuel economy (at engine running temperature) by reducing friction when the engine is running.

I've moved from a 10w40 engine oil down to a 10w30 semi-synthetic engine oil for fuel economy reasons. The Ford Falcon AU Series 2 that I own uses 10w30 to 10w50. However the Series 1 AU Falcon initially came out with a 5w30 engine oil, I'm not entirely sure why they changed it to a 10w30 however the engines are identical (from EB-AU the engines never changed, 4 generations) so I suspect that it was because of premature wear upon startup.

I asked the dealer about whether using 5-30 or 10-40 would make sense and the answer was a definite no. The handbook actually says that all these and also 20-50 is 'acceptable' and then adds the disclaimer that although 0-20 is the preferred range, it may not be suitable for continuous high speed driving (or words to that effect).

0w20 would be too thin during high speed driving I bet. That is what they are trying to get at, because the second number is 10w lower than 0w30 and its the second number which is your engine oil thickness at operating temperature (and highway driving is mostly running at partial throttle)

And the dealer is in the buisness of selling cars. I would just bump it up to 5-30 once its out of warranty coverage.

I wouldn't use any xxw40 oil even in my cars here in Australia. Too thick. The older cars in the 1980s used to use 15w40 oil, this is not the dark ages anymore and we can skimp here or there. We aren't running pushrods anymore.

Beware that when changing engine oil thicknesses do so in small increments or decrements, not sudden changes, and never go outside the factory recommended ranges, don't just go to a store and buy the thickest oil there is because "it will provide better protection". You should only ever use thick oil in engines which are running on tracks where they are at full throttle all of the time and have significant modifications done to them to increase power output (such as a supercharger/turbo).

If your engine is unmodified then you should never go outside the factory recommended specs, they are that way for a reason, for driving on the roads in normal conditions.
 
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Joined 2017
Well worth the watch: YouTube

"SAE 5" and "SAE 30" are both single-grade oils and are obsoleted due to the multi-grade oils that we use today. In the video he is just using them as examples.

Motor oil - Wikipedia

So.. in the simplest terms possible. All oils thin as they warm up. However more modern multi-grade oils don't thin as fast as single-grade oils used to. Hence the reason why we have multi-grade oils today, or, 10w30 instead of just "SAE 30". This was done to prevent the oil from pushing out from in between tight spaces inside of the engine and causing metal-on-metal contact when at operating temperatures.

So its not really a bell curve but that kind of makes it easier to understand, at least it does for me.

The best method of prolonging engine life is to simply replace the engine oil often, the more often you do it the better it will be. Don't leave it to the change interval every time. If your engine oil is black then swap it out.
 
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I raced turbocharged 2.2 liter Dodge cars back in the 1980's and early 90's. I spoke to Carroll Shelby on the phone a couple of times during the years he worked with Chrysler and created some wicked FWD Chargers with his name on them.

Using his advice I had squeezed about 220 HP from my little engine (common now, but not so in the 80's) but began to blow up the manual transaxles frequently. During a discussion with Shelby he asked me what lubricant I was using. I replied that I was using the automatic transmission fluid specified in the owners manual.

He told me that was done to squeeze 1/2 MPG better fuel economy out of the car during the EPA test cycle, use Mobil 1 synthetic oil, it's a much better lubricant. I still broke transaxles, but not near as often. I ran Mobil 1 synthetic oil in the engine because it doesn't cook itself to ash inside a turbocharger. I lived in a hot climate and beat the little engine hard (7200 RPM shifts) catching 5.0 liter Mustangs. I used 10W30 Mobil 1 in the engine and transaxle. I did a tear down every year or two and nothing much in the engine ever broke. I fed it a new timing belt every tear down because it's far easier to do when the engine is out of the car.

Due to my experience with Mobil 1 during my racing days, I have used it ever since in all my cars. The little 4 cylinder in my Honda Element gets 10W30. 0W30 in the V6 that's in my wife's car.
 
I understand the viscosity/temperature trade off, but when all of the cars come with the phrase “use fuel saving 0wxx”. After some diggging I had learned that it was not entirely from the manufacturer.

I get way too much blow-by using the super light oils, have gone to a 5W40 Mobil 1 in order to not have it gum up the rings, this particular car is prone to that. Toyota is supposed to be bullitproof, ha!

Excessive Oil Consumption on 2AZ-FE Engine LSC ZE7 | TOYO Headquarters
 
One point that you guys are intentionally or unintentionally glossing over is that the lower friction, high mileage aspect is partially independent of oil weight. The "API Donut" shows this:

stb3.png


I know this because it is a big deal in the motorcycle world for wet clutch bikes. Text in the "3" area, the bottom of the donut, indicates the presence of friction modifiers, which would result in damage on a wet clutch bike. In the middle weights of oil, you can find both with and without anything written in area "3".
 
Samsung Galaxy Tab A6 7" screen, open-box deal at Best Buy.

I think this was actually a mistake, because the "regular price" quoted was for a lesser model, and the sale price was marked off from that; so I ended up getting it for like 40% off. Somehow I haven't lost a wink of sleep over this. :)

That said, I'm not terribly impressed. It's pretty slow for web-surfing, slower than my S5 phone. Plus, apparently it will only charge properly when connected to an official Samsung USB charger?! That is some basic bull**** right there. If it wasn't so cheap, I'd return it.