CAFE and the USE of Lower Viscosity Motor Oils

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What year was it?

My first car was a Fox Body. Here in BC the 1992 standards for passing Air Care were much more strict than cars 1991 and older. Mine was a '92 and it was a PITA getting that thing through Air Care every year even with the cats on it. A 1991 could be running like garbage and would still pass.

'87, but the limits in Ontario were pretty much across the board, it wouldn't have mattered if it was a '93.
 
I know but my point is CAFE is about individual vehicle models being able to get good mileage, right? Can speccing 0w-16 really bump up the fuel economy in the test so you get to put 36 mpg vs 35?


In the end it is about a car getting good mileage but the thought is applied to the fleet in general. It’s more than just oil too. We concentrate on oil here but a lot of things come together to increase fuel economy. Oil is just one part of the solution.
 
A number of people keep saying that CAFE is the only reason that thinner and thinner oils are being used today. ‘That engines are being sacrificed because of it. If that was true, so what. As long as the engine lasts as long as you own your cars you should be happy. After all, do you not want better fuel economy and less of a carbon footprint for your vehicle?

It would seem that cars with start-stop result in greater wearing of parts. This does not seem to bother anybody.

Then again, it’s been a few decades now and millions upon millions of cars are running these thinner oils. If there is one adverse effect of a medical drug in 40,000 patients then law suits abound. If thin oil was destroying engines would there not be legal issues?

I would venture to guess that there are just as many engine lubrication issues using any oil brand and any oil viscosity as in the past.

AEHaas
The problem with keeping a car for a very long time is not engine longevity but safety. For a long time, I drove a 34-year-old-car, and now, I'm getting a new one every year. It makes a huge difference in terms of safety when you have a latest model with all the advanced electronic safety features. In Japan, you are practically not allowed to drive a car older than about five years. They sell older cars to developing countries. They should do the same here.

It's great if you have an old car and spend a little thought on the oil, but if you have a new car, the discussion is moot. Moreover, the internal-combustion engine will be gone for good in about a decade, and you won't even need engine oil for new cars at that time.
 
The problem with keeping a car for a very long time is not engine longevity but safety. For a long time, I drove a 34-year-old-car, and now, I'm getting a new one every year. It makes a huge difference in terms of safety when you have a latest model with all the advanced electronic safety features. In Japan, you are practically not allowed to drive a car older than about five years. They sell older cars to developing countries. They should do the same here.

It's great if you have an old car and spend a little thought on the oil, but if you have a new car, the discussion is moot. Moreover, the internal-combustion engine will be gone for good in about a decade, and you won't even need engine oil for new cars at that time.
In 10, 15, 20 years in many places you might not even own car due to autonomous electric ride-sharing fleets which will prolly become very common.
 
In 10, 15, 20 years in many places you might not even own car due to autonomous electric ride-sharing fleets which will prolly become very common.
I am skeptical and, to be honest, terrified of full self-driving, but certainly, something like that could eliminate for most people the need to own a car. It would be like the Bird scooter of the future.
 
It's great if you have an old car and spend a little thought on the oil, but if you have a new car, the discussion is moot. Moreover, the internal-combustion engine will be gone for good in about a decade, and you won't even need engine oil for new cars at that time.
This discussion has been thrashed before, and I highly doubt there will be zero new ICE cars for sale in 10 years from now. Give it 25 to 40 years ... maybe.
 
I know but my point is CAFE is about individual vehicle models being able to get good mileage, right? Can speccing 0w-16 really bump up the fuel economy in the test so you get to put 36 mpg vs 35?
You’re correct in that 0w-16 isn’t going to bump your mpg from 36 mpg vs 35 mpg. The numbers I’m about to mention are just for illustration purposes only. Let’s say by using 0W-16 oil, the vehicle gets .001 mpg better compared to 0W-20 . Obviously the vehicle operator won’t notice such a minuscule increase, and it’s not enough to raise the MPG a full MPG. However, when you sell a million vehicles in a given year, that .001 mpg increase per car adds up to a lot of saved CO2 and barrels of oil from being used. Then consider the fact that 5W-20 has been factory fill since around 2001 for a few automakers, assuming those vehicles were serviced with 5W-20 their entire lifespan, that is a large amount of CO2 being prevented from being released into the air.
 
In 10, 15, 20 years in many places you might not even own car due to autonomous electric ride-sharing fleets which will prolly become very common.
 
California and Europe are very serious about it. Other states in the US? Probably not as fast.

They better upgrade the grid. My neighbor is growing weed in his garage and when the utility company came by during a storm, they commented how cooked that guy’s lines are. Imagine millions of cars plugged into the grid. Here in Cali, we have rolling black outs as it is. Time to go to nuclear power for electricity generation or we won’t make it. Because the energy density in gasoline is ten fold compared to a similar sized battery, I highly doubt it’s on its way out just yet. Remember, highly advanced economies burn a ton of fossil fuels. 3rd world and developing countries burn little.
 
I’ve always wondered if the oil usage issues we keep hearing about is because of thinner oil?
What are those issues? I don't hear about "oil usage issues." Well, I do hear about issues of fuel dilution ... but is that an oil issue or an engine design issue?
 
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Fuel economy benefits from thin lubricants, not just engine oil, but gear, transmission and engine , may be dependant on the duty cycle of the vehicle. For example, the average speed over 10 years on my 2500 GMC Duramax is 43 MPH. The average cold start to cold start cycle is over 100 miles. I never use the truck for runs to the store for cigaretts n beer. If for some reason I'm stuck in traffic, I'll turn the engine off. The truck loves to climb hills. Home is 2,000 feet above the city with a 14% grade in one 2 mile section. The sump capacity is around 11 US quarts. 15w40 is the standard fill.
How is my truck's duty cycle different from your vehicle?

Just for a "back in the day" comparison, my parents 69 Chev station wagon with a T400 and 396 265 HP had a sump capacity of 5 US quarts including the filter. 10w30 was the standard and fuel dilution over the top during winter and city driving, 2 miles each way to work & back.
 
I’ve always wondered if the oil usage issues we keep hearing about is because of thinner oil?
No, they are virtually all German cars, which use thick (HTHS ≥ 3.5 cP) oil. Nevertheless, it has nothing to do with the oil.

 
Heres some real oil consumption, which the manufacturer (per manual) says is normal.

 
Can someone explain to me, how does a thinner oil get CAFE points? I get it, thinner oil less drag less parasitic loss better mpg. But when the cars run the fuel economy tests is the 0.1 mpg better even noticeable? Or does calling for a thinner oil help ensure that the cars are more likely to actually get decent mpg in the real world? What am I missing
It's greater than .1 mpg. It's actually 1-2 percent over the next higher grade. Now of course for one vehicle that's seems negligible but about 17 million new vehicles are sold in the US every year. So extrapolate the 1-2 percent over 85 million cars (vehicles sold over last 5 yrs and on the road today) and you can see how the fuel savings adds up.

Now add stop-start which by itself can increase fuel savings up to 8%. So now that big V8 is getting up to 10 percent better fuel efficiency. That's 2-3 mpg or an extra 30 miles per tank.
 
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A number of people keep saying that CAFE is the only reason that thinner and thinner oils are being used today. ‘That engines are being sacrificed because of it. If that was true, so what. As long as the engine lasts as long as you own your cars you should be happy. After all, do you not want better fuel economy and less of a carbon footprint for your vehicle?

It would seem that cars with start-stop result in greater wearing of parts. This does not seem to bother anybody.

Then again, it’s been a few decades now and millions upon millions of cars are running these thinner oils. If there is one adverse effect of a medical drug in 40,000 patients then law suits abound. If thin oil was destroying engines would there not be legal issues?

I would venture to guess that there are just as many engine lubrication issues using any oil brand and any oil viscosity as in the past.

AEHaas
I don't mind a lower viscosity lubricant specification IF the engine is a good production sample and it runs fine on it; it is widely agreed that a lower HTHS will sap less torque and thus boost calculated horsepower and improve efficiency.
I've had engines that needed "help" beyond their 0W20 oil spec to run quieter and better. And it not just me. Ever notice how many car reviewers testing 4 cylinder cars often state how "noisy and thrashy" the engine sounds when pushed? It's more often than not. My Honda Fit 1.5l did well on the 20 grade, the VW 1.4l ti absolutely did NOT, and neither did a couple of our previous FB2.5 Subaru. the current 2.0l does well on it's specified very thin Idemitsu 0W20 - but it's pistons have a more favourable aspect ratio.

There are and have plenty of class action suites with poor running engine the past decades, I don't think anyone has the savvy to put it on the lubricant grade; it's more at the final destructive effect than the root cause. The fingers of fate are often pointed at design and materials or workmanship failures. "These engines should run on this leichtes Öl; the manufacturer failed to deliver."

- Ken
 
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I don't mind a lower viscosity lubricant specification IF the engine is a good production sample and it runs fine on it; it is widely agreed that a lower HTHS will sap less torque and thus boost calculated horsepower and improve efficiency.
I've had engines that needed "help" beyond their 0W20 oil spec to run quieter and better. And it not just me. Ever notice how many car reviewers testing 4 cylinder cars often state how "noisy and thrashy" the engine sounds when pushed? It's more often than not. My Honda Fit 1.5l did well on the 20 grade, the VW 1.4l ti absolutely did NOT, and neither did a couple of our previous FB2.5 Subaru. the current 2.0l does well on it's specified very thin Idemitsu 0W20 - but it's pistons have a more favourable aspect ratio.

There are and have plenty of class action suites with poor running engine the past decades, I don't think anyone has the savvy to put it on the lubricant grade; it's more at the final destructive effect than the root cause. The fingers of fate are often pointed at design and materials or workmanship failures. "These engines should run on this leichtes Öl; the manufacturer failed to deliver."

- Ken
If an engine sounds "noisy and thrashy" on a thinner oil when pushed, that tells me the oil was too thin. Especially when bumping up a grade solves the problem. Metal banging against metal making noise in an engine is not a good thing.
 
Noisy and the thrashy mean different things to different people. A lot of people are still not used to the sound a direct injection engine makes.

@ARCOgraphite mentioned his Subaru doing well on Idemitsu 0w20. Same here. My Mazda is quiet and smooth on that oil yet when I pull the dipstick I notice I have to have a paper towel handy as the oil tends to drip off. It sounds contradictory but there it is.
 
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