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is 0W-20 really the right oil ?

jmdwifi

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Why would anybody question the weight of the oil? I would think that Mopar knows more about this engine than just about anybody around, and if that's what they say to use, then that's what I'm using.
Why? because I wouldn't put it past a manufacturer to use light oil for gas mileage. They don't care if the engine last past 100K, they just need it to make it 60K. Remember the slant six? bullet proof engine and they quit making it. Just an example. I use the recommend oil, I'm just saying I understand why one would question the oily water.
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Why? because I wouldn't put it past a manufacturer to use light oil for gas mileage. They don't care if the engine last past 100K, they just need it to make it 60K. Remember the slant six? bullet proof engine and they quit making it. Just an example. I use the recommend oil, I'm just saying I understand why one would question the oily water.
Because first and foremost, it's the engine that they designed. If they give bad information, then that will flesh itself out as the engine gets along in mileage. But, they should be the ones who know what is best for the engine. As somebody else already said, we're not molecular scientists, and some of them are. If they feed us bad information, then I'm sure somebody will file a class action lawsuit at some point. I understand that there are a lot of guys here that think they know best, that they will put whatever oil in that they damn well please, but I sure don't want to read later about those same people who come back and slam Stellantis because of an improperly maintained engine.
 

seven30

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Why? because I wouldn't put it past a manufacturer to use light oil for gas mileage. They don't care if the engine last past 100K, they just need it to make it 60K. Remember the slant six? bullet proof engine and they quit making it. Just an example. I use the recommend oil, I'm just saying I understand why one would question the oily water.
The slant six was one of the great engines. But one with 100k on it was rare. How long would a 150hp slant six last at 285 hp? I grew up in that era. Cars with 100k were scrap metal. Thats after at least one transmission rebuild along the way. Manufactures were worse back before safety and emission regulations force them to behave. Case in point, We had a 1969 Buick GS 455. Know what brakes it came equipped with? Four tiny iron drums. Its no exaggeration when I say it could accelerate faster than it could stop!
 

jmdwifi

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The slant six was one of the great engines. But one with 100k on it was rare. How long would a 150hp slant six last at 285 hp? I grew up in that era. Cars with 100k were scrap metal. Thats after at least one transmission rebuild along the way. Manufactures were worse back before safety and emission regulations force them to behave. Case in point, We had a 1969 Buick GS 455. Know what brakes it came equipped with? Four tiny iron drums. Its no exaggeration when I say it could accelerate faster than it could stop!
I didn't think about the low HP but I can say, my first car was a 72 duster, then I had a Swinger, then another duster. All slant sixes and all had well over 100k. The bodies were falling apart but engines still running. I'm probably being nostalgic. My first car was my Duster and I worked all summer to buy it. Tan with pea green interior. Looking back, it was ugly as hell but it was mine and I loved it. First taste of freedom.
 

seven30

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I didn't think about the low HP but I can say, my first car was a 72 duster, then I had a Swinger, then another duster. All slant sixes and all had well over 100k. The bodies were falling apart but engines still running. I'm probably being nostalgic. My first car was my Duster and I worked all summer to buy it. Tan with pea green interior. Looking back, it was ugly as hell but it was mine and I loved it. First taste of freedom.
I had a 67 Dart second hand with the slant six. passed down to little brother then one of his friends. Then his friends sister. Lost track after that but it would not die. I think that engine was also in some of the Dodge trucks too.
 

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AmishMike

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We can thank Mercedes for the slant six;)
Have manufacturers started dictating what oil a dealership must use? I was at a dealership into the mid 2000’s and we had Kia through Jaguar, none of them told us who to buy oil from. I now run a fleet of buses and we do a lot of research on oil and a lot of lab testing. Being school buses, they stop and go for 180 days, sit over weekends and the summer. As much as I hate high paraffin oil in a street car or race car, it sticks to cylinder walls which really helps with start up. Yes, a Cummins will go a million miles over the road but only 25-30% of that in a stop and go bus or trash truck before considering rebuild.
We test our oil to find wear patterns and adjust blends accordingly. Sometimes it helps, sometimes it costs us money. Not every bus is driven the same so we shoot for the masses and repair the fringes. Our engines take 19-26 qts depending on year etc. and I guarantee we pay more per gallon than you pay at the big box stores.
As it was said earlier, they design an engine/oil combination for 99% of the market.
 

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Why? because I wouldn't put it past a manufacturer to use light oil for gas mileage. They don't care if the engine last past 100K, they just need it to make it 60K.
For one thing, selling 100k and 125k warranties is big business for them.
 

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It’s not crazy to think the engineers have to balance longevity vs economy vs economics, among other things.
So a thinner oil will help economy, which is a huge factor nowadays with stricter regulations. Like any carmaker would implement stop/start unless they were forced to!

the real question is whether a thicker oil would make the pentastar last longer for most people, which is probably impossible to answer. And yes, maybe thicker would cause more issues with the newer tolerances and variable timing, etc.
 

seven30

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It’s not crazy to think the engineers have to balance longevity vs economy vs economics, among other things.
So a thinner oil will help economy, which is a huge factor nowadays with stricter regulations. Like any carmaker would implement stop/start unless they were forced to!

the real question is whether a thicker oil would make the pentastar last longer for most people, which is probably impossible to answer. And yes, maybe thicker would cause more issues with the newer tolerances and variable timing, etc.Rem
Remember, a thicker oil does not mean more wear protection so no benefit there.
 

seven30

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We can thank Mercedes for the slant six;)
Have manufacturers started dictating what oil a dealership must use? I was at a dealership into the mid 2000’s and we had Kia through Jaguar, none of them told us who to buy oil from. I now run a fleet of buses and we do a lot of research on oil and a lot of lab testing. Being school buses, they stop and go for 180 days, sit over weekends and the summer. As much as I hate high paraffin oil in a street car or race car, it sticks to cylinder walls which really helps with start up. Yes, a Cummins will go a million miles over the road but only 25-30% of that in a stop and go bus or trash truck before considering rebuild.
We test our oil to find wear patterns and adjust blends accordingly. Sometimes it helps, sometimes it costs us money. Not every bus is driven the same so we shoot for the masses and repair the fringes. Our engines take 19-26 qts depending on year etc. and I guarantee we pay more per gallon than you pay at the big box stores.
As it was said earlier, they design an engine/oil combination for 99% of the market.
You must be thinking of the old 300SL with mechanical fuel injection. Always drooled over that one.
 

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Am I correct, 0W oil's today are synthetic based only?
 

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Am I correct, 0W oil's today are synthetic based only?
No. I've found some 0wxx racing oils that are not synthetic and some 0w oils are partial synthetic.
But they don't seem to be common.
Castrol says all 0w20 oils are synthetic or partial synthetic.

The non-synthetic oils I found were more like 0w40 so it's likely a matter of mineral oils not flowing, being small enough.
That being said - other than Pennzoil and perhaps some others, synthetic oil starts with the same oil base, so isn't it a bit contradictory?
Synthetic oil, other than a few, are made with crude oil stock to start with.
So to meet the 0w20 specs, it takes at least partial synthetic oil to meet that.
Heavier 0wxx oils may be mineral or a mix.
The breaking point is somewhere above 0w20 which must have at least some synthetic to it.
 
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DanW

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Am I correct, 0W oil's today are synthetic based only?
I think any with the proper API rating for passenger vehicles are, but for sure all 0w20s I've seen on the market today are. Pennzoil Gold was marketed as a semi synthetic but still had some synthetic base stocks. It isn't available anymore.
 

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To review:

- The "0W" indicates the engine will have the protection of a Zero weight oil when it's started cold in "Winter".

- The "20" indicates the engine will have the protection of a Twenty weight oil when it is at operating temperature.

- Thus, a 0W engine oil offers outstanding protection when starting the engine in cold weather. A larger number will not be an improvement here.

- A 20 will give the engine plenty of protection while letting it get to where it needs to be and also providing better MPGs. It doesn't mean the manufacturer is letting the engine wear out faster so it gets better MPG.

Myths:

- "Heavier oil is better." Nope. As mentioned, modern gasoline engines have very tight tolerances. If the manufacturer says a 0W-20 is all you need, that's all you need.

- "Multi-grade oils are junk." Nope. Modern, multi-grade motor oil is pretty amazing stuff. It offers far superior protection over a single-grade oil. The additives that make it a multi-grade oil do break down. And the the greater the difference between the two numbers, the faster those additives break down. But if you change your oil at regular intervals, like at 5,000 miles, this is not an issue.

- "Racing oil is good for a race engine, so it's good for a street engine." Nope. Actual racing oil doesn't have detergents to keep the engine clean. A race car will get the oil changed after every race. And a race engine is designed with completely different tolerances than a street engine. (Some racing oil, like Valvoline VR-1, has a street version which is fine for a street engine. It has extra anti-foaming agents. It's also good for older engines with flat tappet cams that need zinc.)
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