tbh you've kind of missed the point of the thread, which in essence is if the exact type/spec isn't available, is it ok to use alternatives that might be suggested e.g. on oil checker websites etc. I don't think anyone's advocating taking the advice of 'randoms on the net'.
0W20 vs 0W30 oil
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More than you evidently know about, or are choosing to ignore.
It certainly did! Buying the right oil is much harder now. Sometimes, the manufacturer-specific standards deliver a tangible benefit - for example the VW "long life" oil standard. If you do big miles, it might be worth paying the extra for the "long life" stuff, but if you don't do enough miles in the year, there's nothing wrong with using the cheaper stuff.
Before synthetic oils were invented, oil was just "oil" really, and it was only the viscosity that varied.
Thin oils are specced by the oem to reduce fuel consumption.
Either 5w30 or 5w20 in the correct acea spec will be fine, the specs you mentioned are covered by in both grades by various manufacturers, but best to get a bottle of oil the same as what the engine was filled with at service. But as has been mentioned, in an emergency a litre of some type of oil is better than no oil
Either 5w30 or 5w20 in the correct acea spec will be fine, the specs you mentioned are covered by in both grades by various manufacturers, but best to get a bottle of oil the same as what the engine was filled with at service. But as has been mentioned, in an emergency a litre of some type of oil is better than no oil
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I thought it was to reduce drag in the engine and therefore get better fuel consumption as well as reducing emissions?
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It's not about oil consumption. It's about fuel efficiency more than anything.
Look at Vauxhall and vag official oil consumption figures where a ltr of oil per 1000 miles is deemed acceptable
Look at Vauxhall and vag official oil consumption figures where a ltr of oil per 1000 miles is deemed acceptable
Your right, I meant fuel consumption but was also thinking about oil consumption so wrote oil consumption.
Sorry about that.
It's definitely not to do with oil consumption, Ive amended my post for accuracy.
It's absolutely entirely down to CO2 emissions. Nothing else matters to the manufacturers now. An extra fraction of an MPG off the official fuel consumption figure is neither here nor there, but an extra couple of grammes per km off the official combined CO2 figure would have most emissions engineers willing to sell their own mothers these days - they're absolutely desperate!
Remember the regulations work by adding up the "combined" CO2 figures for all the cars that they have sold in a year, and dividing it by the number of cars. That gives a "fleet average" CO2 figure per car. The regulations set each company's average for 2021 and then imposes a percentage reduction target on that, so in 2022, their fleet average CO2 figure needed to be "x"% lower than it was in 2021, if not, they got fined (last time I looked, I think it was £86) per car, per gramme of CO2 over the target! In 2023, the target reduced compared to 2022, and again in 2024 and 2025 and it will do so again this year.
The manufacturers have had all the low-hanging fruit now - low rolling resistance tyres, stop-start, low viscosity oils, wet belts... This is why we're seeing smaller and smaller engines, being worked harder and harder to keep the power output. As a further kick in the &^%$, the public turned their backs on diesels (which are inherently better on CO2 but have disadvantages when it comes to air quality emissions), so the the fleet average CO2 figures actually went up slightly, as a result. They're on the ropes now!
Remember the regulations work by adding up the "combined" CO2 figures for all the cars that they have sold in a year, and dividing it by the number of cars. That gives a "fleet average" CO2 figure per car. The regulations set each company's average for 2021 and then imposes a percentage reduction target on that, so in 2022, their fleet average CO2 figure needed to be "x"% lower than it was in 2021, if not, they got fined (last time I looked, I think it was £86) per car, per gramme of CO2 over the target! In 2023, the target reduced compared to 2022, and again in 2024 and 2025 and it will do so again this year.
The manufacturers have had all the low-hanging fruit now - low rolling resistance tyres, stop-start, low viscosity oils, wet belts... This is why we're seeing smaller and smaller engines, being worked harder and harder to keep the power output. As a further kick in the &^%$, the public turned their backs on diesels (which are inherently better on CO2 but have disadvantages when it comes to air quality emissions), so the the fleet average CO2 figures actually went up slightly, as a result. They're on the ropes now!
