0w-30 over 5w-30?

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I'm sure it's been asked before, but here goes: I was made aware of Mobil1 12 dollar rebates thanks to BITOG and picked up 2 5 quart jugs of 0w30 for around $10 each. My f150 ecoboost calls for 5w30 and I just changed to the 0w30 tonight for the winter, it gets [censored] cold here in SD. I thought to continue to use 0w30 in the winter and deplete my stash of QSUD 5w30 in the summer. Is there any reason why it wouldn't be beneficial to continue to use a 0w30 year round instead of 5w30 in the summer after my 5w30 is gone?
 
From a practical standpoint there's no difference. You can get into a discussion about VM's and super cold temps like Jimmy mentioned..but that's like sooo esoteric stuff. Just do as you've outlined.. you'll be totally fine.
 
0w30 is fine in the summer too ... and you might even get a couple of tenths of a mpg better fuel economy. That is what M1 AFE (Advanced Fuel Economy ) 0w20/30 advertises. The 0w oil is slightly thinner than a 5w oil at cooler temperatures, so in the engine warm-up phase, there is slightly less drag and pumping loss with the 0w oil. Even in summer.

But, if you want to get all technical, here goes in a very basic sense.

Any multi-grade oil is a compromise. 0w oils are built to work well at extreme cold temps ( 0*F and colder ) . They will always be synthetic, and start off with a thin base oil, often using a mix of ingredients to get that cold flow ability. And that works well when it's cold. To get the hot temperature characteristics of a 30 grade oil, they need more additives to keep the oil from thinning too much at hot temperatures. These are called viscosity index improvers ( VII ) . Almost all multigrade oils use these additives to achieve the cold - hot characteristics desired. 0w oils usually use MORE of these additives. Over time these additives can wear out, or be broken down, possibly leading to oil that is sheared down to a thinner viscosity when hot, and possibly leaving deposits in the engine.

A straight 30 grade oil has ZERO VII additives, is very shear resistant and stable, and works very well when outside temperatures stay well above freezing. If it gets cold, the straight grade oil gets extremely thick, much thicker than a multigrade oil. It works well when HOT, but might not work at all when cold.

A 5w30 oil typically has a thicker base oil and less VII additives than a 0w30 oil, so theoretically it should be less prone to shearing and be more stable. A 10w30 again has even thicker base oil and has less additives than a 5w30, and a 15w30 (yes, they exist ) will have even thicker base oil and less additives than the 10w30, so it should be again less prone to shearing and break down.

So, IDEALLY, you could run a10/15w30 in the summer, for 30 grade hot temp viscosity, but with less VII additives to potentially break down with use, and use an 0w30 in the winter, for better extreme cold flow properties, and still have that 30 grade hot temp viscosity, with the risk of the oil thinning out through shearing and breakdown.

However, most modern 0w oil are built very well, using a complex blend of different (often more expensive) groups of oils, with better engineered additives every generation. They might in practice be SLIGHTLY less stable than a 5/10w oil, but for most applications, will work just fine year round.
 
A 15w30 oil ...

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I read somewhere that you can use a 0W-30 in any vehicle that calls for 5W-30 or 10W-30 without any problems. It's gets very cold in the South Dakota winters we know that! Ha!
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Either 0W30 or 5w30 should be fine. Having said that in South Dakota I might be inclined to go with the 0W30 in the event of a real cold snap. I'd have no problem running it all year.
 
Have a look at M-1 0W40 Euro blend. When it goes on sale for $28 Canuck bucks (.76 USD) for a 5 liter jugs I buy several for company trucks, which includes F150 eco boosts and 6.0L GMCs.
 
SDGolden: As stated above; you'll be fine. My '05 Ranger (lifelong 5W-30 recipient) got 0W-30 (synthetic leftovers) and the engine quieted down immediately.
It made me wish I hadn't logged 1,500 miles before changing it. I'm considering going to a 0W-40 down the road but we'll see.

userfriendly: Let's take "Canuck bucks" and shorten it to "Canbucks". CANBUCKS...it's a natural. Why hadn't anyone thought of that before?

In fact, spell it graphically. "maple leaf, A,N,B,U,C,K,$".

Cheers
 
And real synthetic base oils like PAO are supposed to be easier to make into multi-viscosity lubricants with less VI content than non-synthetic oils. So modern synthetic 0W-30 is really a very stout lubricant.
 
It was only 3-7 yrs ago that some of the 0w-30's were nearly 40 grades. Castrol got the most notoriety with their Belgium Edge 0w-30 full synthetic (SL and SM specced?). I guess with the shift to SN and SN+ these may no longer exist. But it wasn't long ago that performance 0w-30's were much thicker at normal operating temps than the 5w-30's (11.0-12.0 cSt at 100 deg C vs. 9.5-10.5). No doubt some of old stuff is still in people's oil stashes.
 
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Several members only use 0w-30. (harryj and One Eyed Jack to name two) No harm in doing so and as mentioned it is a solid oil.

Come to think of it, haven't seen OneEyedJack in awhile; hope he's doing ok.
 
Originally Posted by Boomer
And real synthetic base oils like PAO are supposed to be easier to make into multi-viscosity lubricants with less VI content than non-synthetic oils. So modern synthetic 0W-30 is really a very stout lubricant.



I agree ^^^^.

Castrol 0w30 is actually a high percentage PAO oil that meets some very tough specs...
 
Rare to none is the synthetic group iv/v
0W, 5W-30 ILSAC GF5 lube.

I know of none easily available to grab at WM or advance or Target

Mobil 1 0w30 is a minority synthetic blend, not full synthetic either.
Forget the advertising on the bottle - its not a technical statement.

The Shell products are majority GTL paraffins and dont perform the same as IV-V synthetics which are poly olefins and poly esters.
 
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You will be fine. The owners manual states that you can sub in 0w30 for the winter months. I had contemplated going to a 0w30, but picked up a bunch of Pennzoil Ultra Platinum and Platinum in 5w30. It's a thin oil with excellent cold flow properties as is and it was on sale for $33 CANBUCKS for 5l jug.
 
I've always found it perplexing that some 0w30's like German Castrol and Esso XD3 are actually more viscous (thicker) at 0*F to 32*F (normal winter temps in my area) than some 5w30s....
 
Originally Posted by pbm
I've always found it perplexing that some 0w30's like German Castrol and Esso XD3 are actually more viscous (thicker) at 0*F to 32*F (normal winter temps in my area) than some 5w30s....

That is because the winter rating is determined at very low temperatures. Much misunderstanding about what the rating means and is determined.
 
I may be wrong here but my understanding is that the difference between 0w and 5w is around 5 degrees of cold weather performance. When it's -30F, another 5 degrees won't matter much. It's already cold and one should be taking other actions to keep things fluid.
 
Originally Posted by PimTac
I may be wrong here but my understanding is that the difference between 0w and 5w is around 5 degrees of cold weather performance. When it's -30F, another 5 degrees won't matter much. It's already cold and one should be taking other actions to keep things fluid.


A 5w oil does not exceed the maximum viscosity limits at -30*c and -35*c, but becomes too thick to meet these requirements at -35*c and -40*c.

So, only 5*c colder moves the oil from functional to questionable in flow and pumpability.

At temperatures around -30F is where it matters MOST ...
 
Originally Posted by pbm
I've always found it perplexing that some 0w30's like German Castrol and Esso XD3 are actually more viscous (thicker) at 0*F to 32*F (normal winter temps in my area) than some 5w30s....


And you know that how ?
 
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