Which is easier to blend: 10w-30 or 15w-40?

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Good day folks. A co worker asked me about this seeing as he notices fair amount of both grades around still. I said probably are both equally the same to blend. But what do I know.
 
@MolaKule, @HPL Plant Manager or @Tom NJ are probably the most knowledgeable on that topic.
Yeah, I'd say they are about the same, they are both cheap to blend and can be cooked up with Mobil's fancy Group 2, and the 15W-40 can even be made using Group I (AP/E CORE):
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Some of you know that my occupation lets me see engineering data and field test for large diesel engines using current spec 15w40 oils. I’ve always puzzled over this: why are so many massive companies using just some plain Rimula or Delo or Esso 15w40?

Especially for fleets where they buy them buy the drum or tote (After all, a single oil drain on some of these larger speed diesels is 100 gallons, with 50-60 gallon pans being the most common), these oils are likely the cheapest branded and fully formulated oils to make and buy.

Most large mine sites will run an engine to 20k hours and overhaul between 20k and 25k hours.

Most fleets are draining every 1000 hours or so now because they use Eliminators instead of spin on filters. So in round numbers, 20 oil changes at 50 gallons each at $15/gallon or so in bulk, you’re looking at $15,000 total lube oil cost (plus makeup) over the life of a large industrial engine. In that time, the engine will have burned about $4 million worth of diesel fuel.

If these cheap oils will keep the engine going 20k hours, how long would they last on Delvac 1 or HPL HDEO?
 
I’ve always puzzled over this: why are so many massive companies using just some plain Rimula or Delo or Esso 15w40?

Especially for fleets where they buy them by the drum or tote ..., these oils are likely the cheapest branded and fully formulated oils to make and buy.

If these cheap oils will keep the engine going 20k hours, how long would they last on Delvac 1 or HPL HDEO?
It's really up to the blender/marketers of the premium/boutique oils to make their case to the end user by presenting their relevant data and arranging trials. They are the only ones who know the formulations and capabilities of their oils, and what performance benefits can be expected. In the end it is not the cost of the lubricant, but the cost of lubrication that matters, and the user/buyer must be shown and convinced of the difference.
 
Can someone answer this for me: would it be better or easier or cheaper to use rerefined basestocks? As most of BITOG knows I’m very interested into rerefines oils/lubes.
 
Can someone answer this for me: would it be better or easier or cheaper to use rerefined basestocks? As most of BITOG knows I’m very interested into rerefines oils/lubes.
Rerefined oils are mostly Group II and are not necessarily cheaper for reasons I have explained in other threads. As for quality, I think rerefined oils are of equal quality as mainline refined oils. Rerefined oils with a quality DI package are on par with other formulated oils using Group II bases.
 
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ROI rules. There's a reason they're not mainstream.
One of the reasons is the stigma rerefines oils get. Most of my co-workers; wjen I asked them if they would use a re refined motor oil said “nah, that’s garbage oil!”

So, I’ve learned that most consumers are ignorant and they always will think an oil that’s even say 50% rerefines is bad. It really is a shame I think.
 
One of the reasons is the stigma rerefines oils get. Most of my co-workers; wjen I asked them if they would use a re refined motor oil said “nah, that’s garbage oil!”

So, I’ve learned that most consumers are ignorant and they always will think an oil that’s even say 50% rerefines is bad. It really is a shame I think.
The consumer's ignorance does not make refining oil any cheaper or more expensive. If there were any clear financial advantage to it, we would get it on the shelves. Margarine, anyone?
 
Well, I always thought redefining oil from automobiles with an oil filter would be somewhat easier than refining crude oil. Shows what I know 🤣
 
If these cheap oils will keep the engine going 20k hours, how long would they last on Delvac 1 or HPL HDEO?
What are the failure modes? It's possible they're not lube related and a more expensive lube would not add life.
That's also the case for most on road vehicles IMHO.
I'd be surprised if UPS, USPS, Wal-Mart, etc are using lubes rated beyond the engine spec.
 
What are the failure modes? It's possible they're not lube related and a more expensive lube would not add life.
That's also the case for most on road vehicles IMHO.
I'd be surprised if UPS, USPS, Wal-Mart, etc are using lubes rated beyond the engine spec.
That's the puzzling thing. The main fail modes are wear and deposits (esp hard carbon on piston crowns and rings) which accelerate that wear. Both are things I'd expect to see a marked improvement with a premium synthetic HDEO.

Heck, I've seen the counterexample-- QSK50 in a Hitachi excavator went nearly 50% beyond expected life to overhaul on Delvac 1 and GTL diesel fuel and everything looked immaculate.
 
What is the definition of "easier to blend"?

Wouldn't this depend on which approvals or spec each oil has to pass or what kind of performance is required?
 
What is the definition of "easier to blend"?

Wouldn't this depend on which approvals or spec each oil has to pass or what kind of performance is required?
Definition means which oil takes less time, materials etc to blend. SO, which one is easier to blend period
 
If you mean blending ease, they are equal - just heating and mixing liquids in most cases. Ease of formulating, testing, cost and availability are different matters.
What's going to drive whether you see them in stores is whether or not people buy them. And right now, there are enough people driving older cars that spec 10w-30, or people who are just used to using it, such that it remains in stores. 15w-40 is typically a diesel grade, so I would imagine that a lot of diesel pickups and equipment (stuff like backhoes, etc.).

I was going to say something about cheap people, but at least at my local Wal-mart, the price seems to be primarily determined by the brand and its market positioning rather than the grade. 10w-30 isn't materially cheaper than 0w-20 across the board, but Supertech is universally cheaper than Quaker State, for example.

As far as blending goes, I would imagine (and I could be very wrong) that part of being a motor oil base stock is the ability to actually blend with other motor oil basestocks without needing some kind of helper chemical or anything. So at that point, it's really just figuring out what set of base stocks you want to use along with your additive package to hit the standards/performance/price targets. There's probably a fair bit of both art and science involved in doing it right.
 
What's going to drive whether you see them in stores is whether or not people buy them. And right now, there are enough people driving older cars that spec 10w-30, or people who are just used to using it, such that it remains in stores. 15w-40 is typically a diesel grade, so I would imagine that a lot of diesel pickups and equipment (stuff like backhoes, etc.).

I was going to say something about cheap people, but at least at my local Wal-mart, the price seems to be primarily determined by the brand and its market positioning rather than the grade. 10w-30 isn't materially cheaper than 0w-20 across the board, but Supertech is universally cheaper than Quaker State, for example.

As far as blending goes, I would imagine (and I could be very wrong) that part of being a motor oil base stock is the ability to actually blend with other motor oil basestocks without needing some kind of helper chemical or anything. So at that point, it's really just figuring out what set of base stocks you want to use along with your additive package to hit the standards/performance/price targets. There's probably a fair bit of both art and science involved in doing it right.
Around me in rust belt lots of folks use 15w40 that’s still dual rated. I’d use Providence as I hate Wal Mart. And Providence HDEO 15w40 is like almost $1~ cheaper than ST. And Providence HDEO comes in a blend 10w30. Wal Mart boycotted 10w30 HDEO’s. I’ve been told that 10w30 uses less VII’s and not sure about 15w40
 
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