Consequence of switching oils, winter vs summer

[Carlostrece]

Is there potential that I'm actually accelerating wear by alternating additive packages that compete with each other?

Potential, yes. Reality, who knows? Why risk it? There's also another factor to consider: Syn vs Conv oil.

Correct my if I'm wrong. AFAIK 15w40 is conventional oil. 5w40 is synthetic oil. So I think 5w40 would be better year round.

Also, I personally think Shell Rotella 5w40 and Mobil Delvac 5w40 are better than Chevron Delo 5w40. However, Chevron Delo 5w40 is good enough. All of the 5w40 mentioned are better year-round than 15w40, IMO.

 

[wlk]

You are in Virginia and barring a freak sub freeze a 15w40 would be fine. Either would work just fine in your climate. I run 10w40 in PA and for the most part see colder temps in the winter and have had zero problems starting w the 10w40. Just let it warm up for a few minutes before pulling out of the driveway

 

[johnmyster]

Potential, yes. Reality, who knows? Why risk it? There's also another factor to consider: Syn vs Conv oil.

Correct my if I'm wrong. AFAIK 15w40 is conventional oil. 5w40 is synthetic oil. So I think 5w40 would be better year round.

Also, I personally think Shell Rotella 5w40 and Mobil Delvac 5w40 are better than Chevron Delo 5w40. However, Chevron Delo 5w40 is good enough. All of the 5w40 mentioned are better year-round than 15w40, IMO.

I think I've covered the why. Summer towing vs winter cold starting.

No, all of the major players offer a "full syn" 15w-40. Delo XSP, Delvac Extreme, T6.

I am running full syn regardless because I can often buy it for less...even though I realize that the advantages are typically not realized for diesels where long intervals are precluded by soot loading, and even moreso on my conservative intervals.

I'm also not sure you're allowed to say Rotella is better than Delvac is better than Delo and still hang out on BITOG.

In the end sounds like everybody wants to tell me about the weather in my own state and not the original question regarding chemistry.

 

[wlk]

I think I've covered the why. Summer towing vs winter cold starting.

No, all of the major players offer a "full syn" 15w-40. Delo XSP, Delvac Extreme, T6.

I am running full syn regardless because I can often buy it for less...even though I realize that the advantages are typically not realized for diesels where long intervals are precluded by soot loading, and even moreso on my conservative intervals.

I'm also not sure you're allowed to say Rotella is better than Delvac is better than Delo and still hang out on BITOG.

In the end sounds like everybody wants to tell me about the weather in my own state and not the original question regarding chemistry.

Bc the weather is more important than the additives competing against one another. The miniscule amount of leftover oil isn't significant enough to bother with. kschachn stated it in post #6 and JohnnyJohnson stated it best in post #9. I have never seen any motor in my 40yrs of working around vehicles being harmed by switching brand.

 

[johnmyster]

Bc the weather is more important than the additives competing against one another. The miniscule amount of leftover oil isn't significant enough to bother with. kschachn stated it in post #6 and JohnnyJohnson stated it best in post #9. I have never seen any motor in my 40yrs of working around vehicles being harmed by switching brand.

If the weather is more important, then you'll have to argue switching grades with the "just stick with whatever" crowd.

I wasn't asking about the miniscule 1/2 quart that gets left behind.

I was hoping to spark some discussion about tribofilm formation on metal surfaces and if that's constant from one lube to the next and if not, if there's background supporting/against reestablishing it every OCI. But you're right. Anecdotal evidence of someone's surviving beater is what really matters.

 

[Carlostrece]

I think I've covered the why. Summer towing vs winter cold starting.

No, all of the major players offer a "full syn" 15w-40. Delo XSP, Delvac Extreme, T6.

OK.

I am running full syn regardless because I can often buy it for less...even though I realize that the advantages are typically not realized for diesels where long intervals are precluded by soot loading, and even moreso on my conservative intervals.

OK.

I'm also not sure you're allowed to say Rotella is better than Delvac is better than Delo and still hang out on BITOG.

I didn't say Rotella is better than Delvac. I said I personally think Rotella and Delvac are both better than Delo. Saying "I personally think" is the same as saying IMO. I can state my opinion.

In the end sounds like everybody wants to tell me about the weather in my own state and not the original question regarding chchemistry.

My entire first paragraph addressed your question about mixing additive packages as well as it can be addressed. I didn't mention the weather in your state.

You asked a question and then berated the people who answered you with helpful intentions. Use whatever you want.

 

[ripcord]

Virginia barely gets below freezing all year long. There's no reason you can't run 15w-40 all year round!

 

[johnmyster]

Virginia barely gets below freezing all year long. There's no reason you can't run 15w-40 all year round!

View attachment 297670

Strangely your graph doesn't reflect the single digits that we actually experience on an annual basis, and the truck does make trips outside of resident homeland. Maybe Richmond (piedmont), Arlington (NOVA) and Norfolk (costal) don't reflect all of the state.

So thanks for pontificating about my weather from 3000 miles away. Owners manual says 0 F.

Question about chemistry still stands.

"Guy is asking question A. I don't really have a response. I'll reply to a question he didn't ask even though he tried to head it off in the first line of his post."

 

[johnmyster]

I didn't say Rotella is better than Delvac. I said I personally think Rotella and Delvac are both better than Delo. Saying "I personally think" is the same as saying IMO. I can state my opinion.

I'm more than interested in your source regarding Delo inferiority as an off-topic tangent. Much more than meteorological pontifications or rough order of magnitude guesses on shear heating delta.

 

[kschachn]

Strangely your graph doesn't reflect the single digits that we actually experience on an annual basis, and the truck does make trips outside of resident homeland. Maybe Richmond (piedmont), Arlington (NOVA) and Norfolk (costal) don't reflect all of the state.

So thanks for pontificating about my weather from 3000 miles away. Owners manual says 0 F.

Question about chemistry still stands.

"Guy is asking question A. I don't really have a response. I'll reply to a question he didn't ask even though he tried to head it off in the first line of his post."

Sometimes on a public Internet board you won't get the answers you wish to hear.

 

[Carlostrece]

I'm more than interested in your source regarding Delo inferiority as an off-topic tangent. Much more than meteorological pontifications or rough order of magnitude guesses on shear heating delta.

I don't remember the source. Supposedly Rotella also flows better than Delo of same grade in cold weather. That could be handy in winter, especially if you choose 15w40 for year-round use. I suggest searching Google for "delo vs rotella" and see what comes up. Read the independent tests and watch the videos. Then decide for yourself.

As for your additive package mixing concern. It would be a non issue if it was the same brand and product in 2 different grades.

However, in your case it's same brand, but different product name. So my answer in your case is: I don't know if there could be an additive conflict. I suggest you choose one of those oils and stick with it year round.

If you're going to use 2 different grades seasonally, then choose 2 with same product name. Such as Rotella 5w40 and Rotella 15w40. Could also use Delvac 5w40 and Delvac 15w40. Could even be Delo 5w40 and Delo 15w40, if those exist.

I mixed Maxlife 5w20 with Maxlife 5w30 in my neighbor's Honda because I put in Maxlife 5w20 at last OCI, and have been topping off with Maxlife 5w30 because it's what I had, and also to slow oil consumption. I'm sure there won't be any additive conflicts because both are same brand and same product name.

 

[Carlostrece]

Strangely your graph doesn't reflect the single digits that we actually experience on an annual basis, and the truck does make trips outside of resident homeland. Maybe Richmond (piedmont), Arlington (NOVA) and Norfolk (costal) don't reflect all of the state.

So thanks for pontificating about my weather from 3000 miles away. Owners manual says 0 F.

Question about chemistry still stands.

"Guy is asking question A. I don't really have a response. I'll reply to a question he didn't ask even though he tried to head it off in the first line of his post."

5w40 works in all (or most) climates in all seasons. It also gives flow and pressure faster at startup, especially in winter. Does anyone think 5w40 can't hold up when towing?

 

[Sequoiasoon]

About the same as changing you brand of TP!

Why would you do that? Is that a seasonal thing also? Winter comfort food vs beach body light fare?

 

[Carlostrece]

Is Delo XSP 15w40 a group 3 oil, or something else? How about Delo XSP 5w40?

Same questions for Rotella T6 and Delvac ESP.

 

[johnmyster]

5w40 works in all (or most) climates in all seasons. It also gives flow and pressure faster at startup, especially in winter. Does anyone think 5w40 can't hold up when towing?

Given that full syn 15w-40 generally have higher HTHS and 100 C viscosities than their 5w counterparts, they certainly aren't going to stand up to fuel dilution (and possibly viscosity shift) any worse. And given that the 15w is the "standard" for this platform (and many historic platforms even if powerstroke and cummins have gotten away from 15w at all operating enviornments) with cold weather being the exception, there's that. And neither of those points has to do with towing.

If you've never towed and watched your oil pressure fall as oil temperatures rise at sustained RPM pulling grades, thinking about how close you are to the point when piston just shut off (check valve closes entirely) then I guess you wouldn't understand. And that's the towing point.

40 grade logic wouldn't imply that one would observe a difference in hot oil pressures between 5w and 15w, but I have and it's a thing. 100 C viscosity rating doesn't mean everything at 120 C and beyond.

And given what I learned on BITOG, higher viscosity always means higher film thickness, which always means less wear. Sounds like a good thing when cold starting temperatures allow. Here's my reference: https://bobistheoilguy.com/forums/threads/is-mobil-1-0w-40-too-thin.397705/post-7333593

Is Delo 15w40 a group 3 oil, or something else? How about Delo 5w40?

Same questions for Rotella and Delvac.

I think it's a safe bet that for oils $9 to $15 a gallon on rebate (T6, Delvac ESP/Extreme, Delo XSP), you aren't getting a majority of grp IV. I'm not really worried about it. Delvac ESP has a reputation for having some good sauce in it. So does Delo XSP.

We do know that Chevron has additive manufacturing in-house, which can only be a good thing.

 

[johnmyster]

Sometimes on a public Internet board you won't get the answers you wish to hear.

Maybe I can find a good climatology board with experts from around the world to disagree with what the thermometer in my back yard says. (Oh wait, that was here.)

When I find them, I'll key them up about potentially competing motor oil additive packages and see where it goes.

 

[Carlostrece]

I misread the OP. I thought he was switching back and forth between Delo XSP and Delvac ESP. Now I understand why he was frustrated with my earlier answers and other peoples answers. OK. My bad. I should have read the OP more carefully.

So here I'd like to revise what I said earlier about mixing additive packages.

Delo XSP 5w40 and Delo XSP 15w40 are (mostly) the same product in different grades. There wouldn't be any additive conflicts switching back and forth between those two.

Delvac ESP 5w40 and Delvac ESP 15w40 are (mostly) the same product in different grades. There wouldn't be any additive conflicts switching back and forth between those two.

Seasonally switch grades if you want to, but I think 5w40 year round is the best choice. I also think Rotella T6 is the best. But those other 2 brands are good too.

Hopefully this time I answered what you were asking about additive packages, plus a little unsolicited advice too.

 

[#18FAN]

I'm just running HPL 5w40 year round Phoenix summer or Wisconsin winter i know I'm covered. I got other things in life to worry about.

 

[Sequoiasoon]

I'm just running HPL 5w40 year round Phoenix summer or Wisconsin winter i know I'm covered. I got other things in life to worry about.

But in what vehicle with what motor?

OP is discussing diesel Cummins 6.7, solid lifter.

 

[Carlostrece]

I'm just running HPL 5w40 year round Phoenix summer or Wisconsin winter i know I'm covered. I got other things in life to worry about.

What's HPL? The use of acronyms without explanation is confusing.