Is 10w-30 "wrong"?

[MichaelRS]

I have an 02 Sienna. I got it in 2012 with 136k on it and now has 189k. I currently use about a quart of oil every 3000 miles.

Ever since I got it I've been using Castrol high mileage 10w-30 in it. Why I chose the high mileage version is probably obvious, but I chose the 10-30 because I live in Orange County, California. For those that don't know, that's an area of the country that even in "cold" winter months in the middle of the night if you get into the 30s (36F = 2.22C) it's pretty rare and actual freezing is even more rare.

The chart in my owner's manual for the 10w-30 says it's supposed to work just fine at above 0F/-18C with the range arrow going above 100F/38C.

So I figured if the upper range for both the 5-30 and the 10-30 is that and since we hardly ever dropped belong below 40F/4C, why not just use the grade that's a little closer to the base stock and go with the 10-30.
Plus, even though in the manual it says the 5-30 is the preferred grade. I figured the 10-30 was just as good as... and they put the 5-30 in there figuring a good many of the people that bought the car would be in very cold climates much of the time and no use switching back and forth between grades.

But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F/29C degrees whereas 5-30 goes up to 96F/35C (okay. That's enough reference. I'm just sticking to Fahrenheit from here on). Both those numbers seem really low for an oil to protect a car in the summer months most anywhere in the US.

So I don't understand what they are talking about when they talk about the different ambient temperatures of the two types of multi-grade oil. I thought all oil that was marked as 30 grade on the high-end would protect the same.

So, have I really been doing my car a disservice all this time by using the 10-30, considering the temperatures I operate in?
Is there really THAT much of a delay of the oil getting up and into the engine to lubricate it from those initial "cold" starts.
Have I been killing my gas mileage at all by using a slightly thicker grade base oil?

 

[Ducked]

I'd use it if I couldn't get anything thicker. Don't think I've ever seen it here though.

 

[CR94]

Originally Posted by MichaelRS
... But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F/29C degrees whereas 5-30 goes up to 96F/35C ... Both those numbers seem really low for an oil to protect a car in the summer months most anywhere in the US.

So I don't understand what they are talking about when they talk about the different ambient temperatures of the two types of multi-grade oil. ...
Methinks the people who wrote your owner's manual know a lot more your engine and about 10W-30 than "some sites" do.

In general, I don't give much credence to the anonymous "they," as in "They say ... ."

Don't worry about it.

 

[Linctex]

Originally Posted by MichaelRS

But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F degrees whereas 5-30 goes up to 96F
.
.

So I don't understand what they are talking about ......


Neither do I.

Though I *will* say I have seen some Ford mod-motor trucks tow some pretty spectacular loads on blazing hot days In Texas while running 5W-20 Dino oil. Does that count?

 

[zeng]

Everything else being equal, I would prefer 10W30 to 5W30 in your application, for lesser VII's among others.

 

[Kamele0N]

Originally Posted by Ducked
I'd use it if I couldn't get anything thicker. Don't think I've ever seen it here though.


+1 15w30&10w30 grades here are reserved for agricultural use

MB 229.5 BMW ll-01 is what protects your engine...but hey...now we are talking about sae40 oils (0w 5w 10w..)

Since you are living in California and you have low sulphur gasoline... Try to get oils with acea c3 ... Bmw ll-04 or even better VW 504 /507 cert... They are usually in 5w30 grade

 

[Garak]

Originally Posted by MichaelRS
But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F/29C degrees whereas 5-30 goes up to 96F/35C (okay. That's enough reference. I'm just sticking to Fahrenheit from here on). Both those numbers seem really low for an oil to protect a car in the summer months most anywhere in the US.

I've seen that on some charts, like the chart for my old Audi; in fact, it was worse. If your manual says it's fine, it's fine. Look here:

According to that chart, SAE 30 wasn't even good enough for my Audi in a Saskatchewan summer.

 

[Cujet]

Try looking up the HTHS numbers for the oil you choose.

Any generalization about 5W-30 vs. 10W-30 is, in theory, meaningless. As both should provide the protection of a 30 viscosity oil at 212 degrees F. A 30 viscosity oil should be between 9.3 and 12.5 Cst at 100 deg C or 212 deg F.

However, better oils have higher viscosities (HTHS) at 150 deg C. This is where conventional 5W-30 oils often fall short of 10W-30.

BUT,,,,, Not all 10W-30 oils have higher HTHS than 5W-30. A quality synthetic 5W-30 such as M1 may be (HTHS Viscosity, mPa•s @ 150ºC) 3.1 and a conventional 10w-30 will generally be 2.9.

I'm of the opinion that the use of a quality oil of sufficient viscosity for the location, and frequent oil changes is always the right answer.

I use 10W-30 M1 in my F150, which calls for 5W-20. My UOA results are superb, and my truck does not have Cam Phaser and Cam Chain problems like so many other 5.4L Ford's locally.

 

[tig1]

A couple of things you may notice with X-50 oil.
1. The engine may be a little more sluggish.

2. MPG may drop a little. I noticed this in my 1990 Ford Tempo when I tried M1 15-50 in my 1996 Merc GM 4.6 compared to M1 5-10-30.

 

[CT8]

Originally Posted by Linctex
Originally Posted by MichaelRS

But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F degrees whereas 5-30 goes up to 96F
.
.

So I don't understand what they are talking about ......


Neither do I.

Though I *will* say I have seen some Ford mod-motor trucks tow some pretty spectacular loads on blazing hot days In Texas while running 5W-20 Dino oil. Does that count?

They are moving back to 30s

 

[Uphill_Both_Ways]

Originally Posted by Garak
Originally Posted by MichaelRS
But then I was researching it some recently and I saw that some sites were saying 10-30 protects your engine up to an ambient temperature of 84F/29C degrees whereas 5-30 goes up to 96F/35C. . . .

I've seen that on some charts, like the chart for my old Audi; in fact, it was worse. If your manual says it's fine, it's fine. Look here:

According to that chart, SAE 30 wasn't even good enough for my Audi in a Saskatchewan summer.

Good grief! The temperature in summer here always climbs into the high 80s F and into the 90s. In August it hit 100. I had no idea 5W-30 discombobulates at 85. Good thing I forgot to plug in the block heater.

I shall have to write a strong letter to Mr. Mobil complaining that his 5W-30 walks off the job at 86 F, and demand he come here and change my car's oil at 85 every morning, then change it back when night falls until cooler weather prevails. He can bring his own flashlight.

Or maybe don't drive an Audi.

 

[Yah-Tah-Hey]

5W-30 Mobil I

 

[ChrisD46]

* I used 10W30 M1 in my Sonata GDI engine (grade is allowed by Hyundai in the OM) for less of a spread / less VII's needed resulting in hopefully less deposits ... Now with 5W30 synthetic Dexos 1 Gen 2 SN+ oils out now I will look to discontinue using 10W30 M1 which does not have the new approvals said to be better for GDI engines which the new 5W30 D1 Gen 2 SN+ synthetic oils have . .
Originally Posted by Cujet
Try looking up the HTHS numbers for the oil you choose.

Any generalization about 5W-30 vs. 10W-30 is, in theory, meaningless. As both should provide the protection of a 30 viscosity oil at 212 degrees F. A 30 viscosity oil should be between 9.3 and 12.5 Cst at 100 deg C or 212 deg F.

However, better oils have higher viscosities (HTHS) at 150 deg C. This is where conventional 5W-30 oils often fall short of 10W-30.

BUT,,,,, Not all 10W-30 oils have higher HTHS than 5W-30. A quality synthetic 5W-30 such as M1 may be (HTHS Viscosity, mPa•s @ 150ºC) 3.1 and a conventional 10w-30 will generally be 2.9.

I'm of the opinion that the use of a quality oil of sufficient viscosity for the location, and frequent oil changes is always the right answer.

I use 10W-30 M1 in my F150, which calls for 5W-20. My UOA results are superb, and my truck does not have Cam Phaser and Cam Chain problems like so many other 5.4L Ford's locally.

 

[rinkevichjm]

5W-30 is a also a gas saving oil. its the reason the Prius uses 0W-20. So yes you have been a pound foolish penny pincher. but the wear is probably from not changing the filter and oil often enough.

 

[kschachn]

Originally Posted by rinkevichjm
5W-30 is a also a gas saving oil. its the reason the Prius uses 0W-20. So yes you have been a pound foolish penny pincher. but the wear is probably from not changing the filter and oil often enough.

A ridiculous post. 10W-30 is perfectly usable in his climate and he's not a "pound foolish penny pincher" in any way.

And what wear?

 

[JLTD]

You've chosen a 30 grade oil with the correct w rating for your climate. Drive on.

 

[MichaelRS]

I thank everybody for their thoughts thus far. Some of those charts, saying that the 10-30 weight gives out it 85 or 95 degrees, like I saw and some sites, are just really weird to me. So that is why I was like, [censored]?

Oh, I use a Royal Purple filter and shoot to change my oil at 5k. Unfortunately that usually ends up at something like 5.6 or .7.

I think what I really need is a oil analysis from Blackstone. My last one was just over 4 years ago at 4.3k and the only thing off was that the copper was just a smidge high and my TBN was 0.6 and it supposed to be >1.0.
At that time they said I could stretch it to 5000 miles. But since I'm routinely going over 5000 miles for my oil changes that's probably not great.

And I'm not really interested, as somebody said before, in being penny-wise and pound-foolish by trying to figureout how I can stretch my oil down to the last mile of its usefulness.
There is the issue of it being an older car with higher miles plus the sludge build-up issues some of these first-generation Siennas have been known for.
So I'm thinking I should probably shoot for the mid 4K's for my oil changes.

I also think I'll switch to that Mobil 1 Extended Performance filter as it is a little cheaper and apparently just as highly rated, or my purpose at my frequency of OCI, as the Royal Purple.

 

[Garak]

Originally Posted by Uphill_Both_Ways
Good grief! The temperature in summer here always climbs into the high 80s F and into the 90s. In August it hit 100. I had no idea 5W-30 discombobulates at 85. Good thing I forgot to plug in the block heater.

Of course, that chart and their ridiculously long OCIs on conventional oil were part of the reason they brought out VW/Audi oil specifications. For my Audi, RP 0w-40 and Delvac 1 ESP 5w-40 were decent year round choices.

Originally Posted by rinkevichjm
5W-30 is a also a gas saving oil. its the reason the Prius uses 0W-20. So yes you have been a pound foolish penny pincher. but the wear is probably from not changing the filter and oil often enough.

10w-30 is also a fuel saving oil by that rationale. Do note that the 5w-30 I'm using in my G37 is significantly thicker at operating temperature than the 10w-30 in my F-150.

 

[JLTD]

Originally Posted by MichaelRS
I thank everybody for their thoughts thus far. Some of those charts, saying that the 10-30 weight gives out it 85 or 95 degrees, like I saw and some sites, are just really weird to me. So that is why I was like, [censored]?

Oh, I use a Royal Purple filter and shoot to change my oil at 5k. Unfortunately that usually ends up at something like 5.6 or .7.

I think what I really need is a oil analysis from Blackstone. My last one was just over 4 years ago at 4.3k and the only thing off was that the copper was just a smidge high and my TBN was 0.6 and it supposed to be >1.0.
At that time they said I could stretch it to 5000 miles. But since I'm routinely going over 5000 miles for my oil changes that's probably not great.

And I'm not really interested, as somebody said before, in being penny-wise and pound-foolish by trying to figureout how I can stretch my oil down to the last mile of its usefulness.
There is the issue of it being an older car with higher miles plus the sludge build-up issues some of these first-generation Siennas have been known for.
So I'm thinking I should probably shoot for the mid 4K's for my oil changes.

I also think I'll switch to that Mobil 1 Extended Performance filter as it is a little cheaper and apparently just as highly rated, or my purpose at my frequency of OCI, as the Royal Purple.



Yeah I cannot say just why those charts indicate a 30 is done above 38°C/100°F...perhaps the manufacturer wants a 40 grade above those temps.

The RP filter is good, but overpriced IMO. You could pay 1/2 and run a Fram Ultra for 2 OCIs.

 

[dave1251]

Originally Posted by CT8

They are moving back to 30s


No Ford is not for the coyote. Ecoboost in some applications.