Viscosities: Mobil 1 5w30 vs 10w30?

[JonnyAbs]

I pulled this info right off their product pages on the Mobil.com website.

Wouldn't you think that their Viscosities @ 40 C would be reversed? 5w30 is thicker. Yes it pours very slightly better when cold, but come on. I feel like two different grades are not needed here considering they are almost the same when cold and the 5w is thicker at operating. Just seems weird to me. I would probably rather run the 10w30, esp in a vehicle that calls for Xw20 and burns oil.

Grade	SAE 5W-30
Density @ 15.6 C, g/cm3, ASTM D4052	0.852
Flash Point, Cleveland Open Cup, °C, ASTM D92	230
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	11.1
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445	64
Pour Point, °C, ASTM D97	-45

Grade	SAE 10W-30
Density @ 15.6 C, g/ml, ASTM D4052	0.859
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	10.4
Flash Point, Cleveland Open Cup, °C, ASTM D92	232
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445	66
Pour Point, °C, ASTM D97	-42

 

[wpod]

Lookup the specs on the 0W-40 European M1 and the M1 high mileage 5W-30.

 

[JT20]

I pulled this info right off their product pages on the Mobil.com website.

Wouldn't you think that their Viscosities @ 40 C would be reversed? 5w30 is thicker. Yes it pours very slightly better when cold, but come on. I feel like two different grades are not needed here considering they are almost the same when cold and the 5w is thicker at operating. Just seems weird to me. I would probably rather run the 10w30, esp in a vehicle that calls for Xw20 and burns oil.

Grade	SAE 5W-30
Density @ 15.6 C, g/cm3, ASTM D4052	0.852
Flash Point, Cleveland Open Cup, °C, ASTM D92	230
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	11.1
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445	64
Pour Point, °C, ASTM D97	-45

Grade	SAE 10W-30
Density @ 15.6 C, g/ml, ASTM D4052	0.859
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	10.4
Flash Point, Cleveland Open Cup, °C, ASTM D92	232
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445	66
Pour Point, °C, ASTM D97	-42

The 5W-30 probably has a higher Viscosity Index.

I see this a lot.. the lower W number usually has a thicker thickness or HTHS (?) than a higher W number. As a result, I am most reserved about ever going 10W.

Should I be?

 

[paulri]

I noticed that their 10w30 HM had an HTHS equivalent to those of a 40 grade. So YMMV depending of course on which of the dozens of 30 grade oils Mobil offers, and which two you are comparing. If you wanted a thick 30, or a thick 10w30, that one would probably be it.

The 5W-30 probably has a higher Viscosity Index.

I see this a lot.. the lower W number usually has a thicker thickness or HTHS (?) than a higher W number. As a result, I am most reserved about ever going 10W.

Should I be?

 

[wpod]

The 5W-30 probably has a higher Viscosity Index.

I see this a lot.. the lower W number usually has a thicker thickness or HTHS (?) than a higher W number. As a result, I am most reserved about ever going 10W.

Should I be?

Oil with less viscosity improvers may be "thicker " between the parts .

 

[JonnyAbs]

Lookup the specs on the 0W-40 European M1 and the M1 high mileage 5W-30.

I was reluctant to do so with no objective stated, but I did so anyway and don't see the point of this goose chase? It was pretty much what you would expect. Are you pointing out that they basically have the same Viscosity @ 40 C? I would expect that being that the European has a higher viscosity at 100 C. It would only strike me as strange if their viscosities at 100 C were reversed.

Grade	SAE 0W-40
Ash, Sulfated, mass%, ASTM D874	1.34
Density @ 15 C, g/cm3, ASTM D4052	0.8456
Flash Point, Cleveland Open Cup, °C, ASTM D92	226
Hi-Temp Hi-Shear Viscosity @ 150 C 1x10(6) sec(-1), mPa.s, ASTM D4683	3.6
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	12.9
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445	70.8

High Mileage:

Property	0W-20	5W-20	5W-30	10W-30	10W-40
Grade	SAE 0W-20	SAE 5W-20	SAE 5W-30	SAE 10W-30	SAE 10W-40
Density @ 15.6 C, g/cm3, ASTM D4052	0.839	0.840	0.852		0.861
Density, 15.6C, g/cm3, ASTM D4052				0.861
Flash Point, Cleveland Open Cup, °C, ASTM D92	224	234	245	239	239
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445	8.8	8.6	11.9	12	15.3
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445			70	80	101
Pour Point, °C, ASTM D97	-51	-51	-45	-39	-42

 

[Rhymingmechanic]

Interesting observation. I have a chart from the SL days, when I stocked up on what was about 10 years worth of oil changes for my Chevy pickup. While I know the 5w-30 has increased at 100 C, I hadn't paid attention to the 40 C number.

Here are the SL numbers:

5w-30
cST@100: 10.0

cST@40: 56

HTHS: 3.08

VI: 167

10w-30
cST@100: 10.0

cST@40: 62

HTHS: 3.17

VI: 147

Flash and Pour points are identical at 224 C and -45 C.

 

[kschachn]

It's hard to understand exactly what the problem is? Grades are just that, a range of acceptable viscosity. The winter rating is not necessarily related to that, as you can see from your example. If viscosity is your only concern then pick the one with a winter rating that is appropriate for your expected starting conditions.

Having said that, not all brands are going to show the same thing as your example. Does it matter?

 

[kschachn]

Oil with less viscosity improvers may be "thicker " between the parts .

Please explain in technical terms what this means.

 

[OilUzer]

Guessing he is talking about the temporary(?) or potential shear of vm under pressure?

 

[JonnyAbs]

Interesting observation. I have a chart from the SL days, when I stocked up on what was about 10 years worth of oil changes for my Chevy pickup. While I know the 5w-30 has increased at 100 C, I hadn't paid attention to the 40 C number.

Here are the SL numbers:

5w-30
cST@100: 10.0

cST@40: 56

HTHS: 3.08

VI: 167

10w-30
cST@100: 10.0

cST@40: 62

HTHS: 3.17

VI: 147

Flash and Pour points are identical at 224 C and -45 C.

These actually make logical sense to me. At a certain point, it seems like they went heavier on each. Actually even heavier on the 5w. Weird.

 

[JonnyAbs]

It's hard to understand exactly what the problem is? Grades are just that, a range of acceptable viscosity. The winter rating is not necessarily related to that, as you can see from your example. If viscosity is your only concern then pick the one with a winter rating that is appropriate for your expected starting conditions.

Having said that, not all brands are going to show the same thing as your example. Does it matter?

I wouldnt think twice if these were 2 different brands. But they aren't. I can't do any better than I already tried to explain why it is surprising. Logically, I think most people would expect 10w30 to be thicker than 5w30, not the opposite and by a decent margin.

 

[farrarfan1]

The HTHS is higher with the 10W-30, doesn’t that technically make it “thicker” than the 5W-30?

 

[kschachn]

I wouldnt think twice if these were 2 different brands. But they aren't. I can't do any better than I already tried to explain why it is surprising. Logically, I think most people would expect 10w30 to be thicker than 5w30, not the opposite and by a decent margin.

I guess I still don't understand why, both are 30-grade oils and fall within the allowances for that grade (that's all I'd expect) Winter rating isn't really relevant here especially when one considers the use of VII.

 

[Patman]

I have been saying this for years now, I don't see the need for 10w30 anymore, when 5w30 can do everything that it can do plus flows better in the cold. The 5w30s these days are built very stable, it's not like 30 years ago when you needed 10w30 because the 5w30s would thin out rapidly.

 

[JonnyAbs]

I have been saying this for years now, I don't see the need for 10w30 anymore, when 5w30 can do everything that it can do plus flows better in the cold. The 5w30s these days are built very stable, it's not like 30 years ago when you needed 10w30 because the 5w30s would thin out rapidly.

I agree with you and I think Shell does too with respect to their Rotella Gas Truck only being available in 0w20, 5w20, and 5w30 grades.

I was trying to explain to some guy commenting on a youtube video that he didn't need 10w30 and that Rotella's 5w30 would suffice no problem for towing. He would not listen.

To be honest, 0w20 and 5w20 seem close enough to me to consolidate also.

 

[JonnyAbs]

I have been saying this for years now, I don't see the need for 10w30 anymore, when 5w30 can do everything that it can do plus flows better in the cold. The 5w30s these days are built very stable, it's not like 30 years ago when you needed 10w30 because the 5w30s would thin out rapidly.

You think the only reason Rotella Gas Truck has both of these grades is to satisfy the consumer that will only buy 0w20 or 5w20? They are so similar, I feel like they should combine into one and call it Xw20

 

[ZeeOSix]

Guessing he is talking about the temporary(?) or potential shear of vm under pressure?

Yes, oils with higher VIIs may lose some HTHS viscosity due to the VIs shearing and causing a viscosity reduction between parts compared to oils with less VIIs.

 

[JT20]

I must not be the only one that goes to the oil aisle, sees 5W-30 next to 10W-30.. and just stared at them, not knowing which one to buy.

Almost like the 10W would be "better."

Because if it doesn't have as much in it to make it meet both its 5W part, or winter rating of 5, AND it's API grade of 30..

But what do I know.

That 10W is right there, side by side. It doesn't seem physically possible that it can have a higher Winter rating and not be thicker, somehow.

But this is just speculation from the guy staring at oil at Walmart, I don't hold any engineering degrees and I drive a forklift. Hey.

 

[kschachn]

I must not be the only one that goes to the oil aisle, sees 5W-30 next to 10W-30.. and just stared at them, not knowing which one to buy.

Almost like the 10W would be "better."

Because if it doesn't have as much in it to make it meet both its 5W part, or winter rating of 5, AND it's API grade of 30..

But what do I know.

That 10W is right there, side by side. It doesn't seem physically possible that it can have a higher Winter rating and not be thicker, somehow.

But this is just speculation from the guy staring at oil at Walmart, I don't hold any engineering degrees and I drive a forklift. Hey.

As much of what in it?

This thread highlights the misunderstanding about the winter rating, what it means and what it does not mean.