Mobil 1 0w40 European Oil......the new 5w30?

It depends on so many variables. The type of engine, pump, condition of the engine, etc to say. I have run 0w40 in engines that had all the things you mentioned that were spec for 0w20 in the USA but 0w40 in Europe with no issues whatsoever.
Most engines even today are built to run on a wide viscosity variation because of climate and operating conditions. I probably wouldnt run a 20w50 in a 0w20 engine but in an extreme climate like the middle east or parts of Australia it possibly would be fine.
 
It depends on so many variables. The type of engine, pump, condition of the engine, etc to say. I have run 0w40 in engines that had all the things you mentioned that were spec for 0w20 in the USA but 0w40 in Europe with no issues whatsoever.
Most engines even today are built to run on a wide viscosity variation because of climate and operating conditions. I probably wouldnt run a 20w50 in a 0w20 engine but in an extreme climate like the middle east or parts of Australia it possibly would be fine.
What engine this is if you don't mind me asking?
 
In my garage, M1 0w-40 is the "Frank's RedHot" of motor oils. My cars, my dads car, my kids cars, etc... If its out of warranty, I dont care what it is, its getting M1 0w-40. Lawnmowers too, except the Kubota in the barn, its a diesel, it gets what its supposed to.
 
Here is a link to pictures of the Australian print of the 2018 Camry Hybrid owners manual.

Toyota says you can 0W16, 0W20, 5W20, 5W30, 10W30 or 15W40 in that VVTI engine


Proof it is more about operating conditions than engine design in most cases, it also dispels the myth "the engineers designed it to run on 0w20" (true and any other grade on the shelf also).
There are a very few engine that are built with "thin oil only" in mind but that seems to be operating condition dependent where they are sold.
 
In my garage, M1 0w-40 is the "Frank's RedHot" of motor oils. My cars, my dads car, my kids cars, etc... If its out of warranty, I dont care what it is, its getting M1 0w-40. Lawnmowers too, except the Kubota in the barn, its a diesel, it gets what its supposed to.

Just curious what you put in your Kubota? My Mercedes turbodiesel loves 0w40 from Castrol, Valvoline, and Mobil 1.
 
I’ve read that the Dodge 5.7 Hemi is sensitive enough to sense if a thicker oil is used and will set a code in the PCM. I believe Dodge updated the PCM logic a number of years ago and it will no longer set a code for the wrong oil viscosity being used. Since the PCM knows the coolant temperature, ambient temperature, oil pressure, and often times oil temperature, it seems understandable that the PCM can programmed to monitor oil viscosity to an extent.
 
I’ve read that the Dodge 5.7 Hemi is sensitive enough to sense if a thicker oil is used and will set a code in the PCM. I believe Dodge updated the PCM logic a number of years ago and it will no longer set a code for the wrong oil viscosity being used. Since the PCM knows the coolant temperature, ambient temperature, oil pressure, and often times oil temperature, it seems understandable that the PCM can programmed to monitor oil viscosity to an extent.

If you ran like 5w-40 in one that spec'd 5w-20 and it hit -30C you could get a code. I think at -35C was the only time former member Clevy was able to get his '06 Charger to set that code (which has no impact on operation) with 0w-40 in the pan.

Since there's absolutely no difference in VCT or MDS operation between the 5.7L that spec's 5w-20 and the 6.4L that specs 0w-40, I suspect the purpose was/is more loosely affiliated with ensuring that the spec oil is being used and little to do with proper operation.
 
If you ran like 5w-40 in one that spec'd 5w-20 and it hit -30C you could get a code. I think at -35C was the only time former member Clevy was able to get his '06 Charger to set that code (which has no impact on operation) with 0w-40 in the pan. ...

Since both are 5W, I assume in your example the KV-30 (minus 30) of the 40 is much? higher than the KV-30 of the 20. No?
 
But a lot of people here preach that your engine will never know if you use a thicker oil, but the Dodge Hemi tells us otherwise.

I agree with @ARCOgraphite. I’ve noticed on cars with VVT that oil viscosity can make a difference in throttle response. My Hyundai with the Theta II 2.4 I used 5w-30 for the first few oil changes because that’s what I had on hand. When I used it all up I purchased 5w-20 and I immediately noticed that the throttle was much peppier when accelerating from a stand still. It took me about a week to get used to the throttle response with 5w-20 oil. I never would have believed it until experiencing it myself but I do believe some engines are sensitive to the oil viscosity being used. FWIW, my Theta II uses an electronically controlled intake VVT actuator so maybe only certain systems are more sensitive than others.
 
Since both are 5W, I assume in your example the KV-30 (minus 30) of the 40 is much? higher than the KV-30 of the 20. No?

Yes, and as soon as the oil starts to warm the difference likely manifests as higher than anticipated pressure as you move away from CCS/MRV limits and into KV territory, as I expect there is an allowance for a brief warm-up period factored in.

From an old Pennzoil PDS I have here, their 5w-20 was 3,860cP at -30C (CCS), whilst Valvoline SynPower MST was 5,500cP at -30C.
 
Is flow of a 0w40 is comparable (close) to say a 5w30 or 5w20 at start up at say 20F to 30F ambient temp?
In other words: it maybe is a no brainer to use a 40 oil in a hot summer, but would you be comfortable using 0w40 in around freezing temps?
 
Last edited:
But a lot of people here preach that your engine will never know if you use a thicker oil, but the Dodge Hemi tells us otherwise.

I agree with @ARCOgraphite. I’ve noticed on cars with VVT that oil viscosity can make a difference in throttle response. My Hyundai with the Theta II 2.4 I used 5w-30 for the first few oil changes because that’s what I had on hand. When I used it all up I purchased 5w-20 and I immediately noticed that the throttle was much peppier when accelerating from a stand still. It took me about a week to get used to the throttle response with 5w-20 oil. I never would have believed it until experiencing it myself but I do believe some engines are sensitive to the oil viscosity being used. FWIW, my Theta II uses an electronically controlled intake VVT actuator so maybe only certain systems are more sensitive than others.

The HEMI infers viscosity from oil pressure based on temperature. If that's out of whack it sets a code. This, as I noted, only appears to be an issue if somebody really goes to town deviating from spec (like running 15w-40) or they are in a location where it gets extremely cold.

As to your other point, this is the problem with the "butt dyno".

The difference in visc at operating between a 5w-20 and 5w-30 is minuscule.

Looking at Pennzoil Platinum:
5w-20: 8.46cSt @ 100C, 45.34cSt @ 40C
5w-30: 10.25cSt @ 100C, 55.2cSt @ 40C

At operating temperature you are off by 2.2cSt.

At only 10C cooler, your 5w-20 is 10.56cSt (90C), heavier than the 5w-30 at 100C.
At only 10C warmer, your 5w-30 is 8.44cSt (110C), thinner than the 5w-20 at 100C.

So, a little more love on the pedal to drive up temperature and your 5w-30 is now thinner than your 5w-20. It's a cooler day? Your 5w-20 is now heavier than your 5w-30 was on a hotter day.

Engines and their systems are simply not that sensitive to viscosity, they can't be! Your VVT would completely crap the bed on a cold start if it can't handle a 2cSt difference at operating temperature. At 10C, your 5w-20 is 186cSt, 22x heavier that at operating temperature!

This is the problem with measures driven by emotion and perception rather than actual scientific data. It's very easy to "feel" something that isn't there when you change a variable and expect something. My 6.4L has more tip-in than my 5.7L, not because it's on a heavier oil, but because it makes almost 100HP more, has a significantly different camshaft profile and has completely different programming.

If you have the capability, track your oil temperature. You can calculate operating viscosity from that using the oil data sheet values for what you are running.

For example, -18C, my oil temp in the Jeep was 71C:
FEE75208-FE83-4AA7-8AD9-C8715B6378C7_1_105_c.jpeg


This means operating viscosity was 26.69cSt, double what it is at 100C. My VCT and MDS both worked normally, despite that fact.
 
Is flow of a 0w40 is comparable (close) to say a 5w30 or 5w20 at start up at say 20F to 30F ambient temp?
In other words: it mabe a no brainer to use a 40 oil in a hot summer, but would you be comfortable using 0w40 in around freezing temps?

Flow is never a concern provided the Winter rating is appropriate for the anticipated ambient temperatures. Providing the pump isn't on the relief, it is moving the same amount of oil per revolution.

A higher visc will result in more drag, which has a small impact (typically immeasurable) on fuel economy. That said, there's no benefit of running a heavier oil than specified if the spec oil provides adequate performance. This is particularly relevant in applications where the oil temperature is thermostatically controlled and thus wide swings are not experienced.
 
Thanks for trying to explain. As I already said, I wouldn’t have believed going up an oil grade would make any difference whatsoever. I have in fact used 30 grade oils in 5w-20 applications and 40 grade oils in 5w-30 applications and NEVER noticed a difference. However, some engines I have noticed an unexpected difference. My Hyundai Theta II it was clearly noticeable. I wouldn’t say it’s my butt dyno in this case.
 
Thanks for trying to explain. As I already said, I wouldn’t have believed going up an oil grade would make any difference whatsoever. I have in fact used 30 grade oils in 5w-20 applications and 40 grade oils in 5w-30 applications and NEVER noticed a difference. However, some engines I have noticed an unexpected difference. My Hyundai Theta II it was clearly noticeable. I wouldn’t say it’s my butt dyno in this case.

Well, even within a given grade you can have a larger difference than the figures we are discussing.

For example, if you look at this chart of 5w-20's from the PQIA:

KV100 varies from 6.8cSt to 9.46cSt, a difference of 2.66cSt.

I'd be more inclined to think that if what you experienced wasn't just butt dyno miscalibration that the more likely culprit would be a change in oil chemistry via the additive package or that the car was just breaking in (if you had bought it new).
 
Well, even within a given grade you can have a larger difference than the figures we are discussing.

For example, if you look at this chart of 5w-20's from the PQIA:

KV100 varies from 6.8cSt to 9.46cSt, a difference of 2.66cSt.

I'd be more inclined to think that if what you experienced wasn't just butt dyno miscalibration that the more likely culprit would be a change in oil chemistry via the additive package or that the car was just breaking in (if you had bought it new).

The 5w-20 valvoline advanced SN PLUS was when I noticed the change in throttle response. All the other oils I’ve used have been 5w-30 SN synthetic ranging from PUP, QSUD, and Havoline Prods.
So could be related to the oil additive chemistry, but I know most people say that can’t be so.
 
The 5w-20 valvoline advanced SN PLUS was when I noticed the change in throttle response. All the other oils I’ve used have been 5w-30 SN synthetic ranging from PUP, QSUD, and Havoline Prods.
So could be related to the oil additive chemistry, but I know most people say that can’t be so.

Was the engine/car new or just new to you?

I'd be more likely to accept chemistry as a possible factor versus a 2.2cSt difference in viscosity ;) If the car/engine was a used purchase (so just new to you) it's also possible there were some deposits that were removed by the change in chemistry, which could explain it.
 
Back
Top