Any reason to use 10w-30 over 5w-30? (modern oils)

[Garak]

Originally Posted By: ndfergy
Is there any application today in which a 10w-30 is still preferable to a 5w-30?

Yes, a manual transmission vehicle. When you depress the clutch you're putting a lateral force on the engine - specifically the crank thrust bearings. Although the KV100 may be lower with a 10W the specific gravity/density, and in all probability the HTHS, is higher. A heavier oil is harder to displace.

That extra 0.1 HTHS isn't much. Again, why an ILSAC 10w-30 over an A3/B4 5w-30 or 0w-30 or HDEO? Those will at least have an HTHS of 3.5 or greater, not 3.1 or 3.0.

 

[ndfergy]

My car is still under warranty so I'm limited to SN/GF-5 oils. However, I'm more than satisfied with what I currently use.

MS1000 10W30: HTHS 3.2; PP -33C; FP 222; density 0.869; NOACK not listed but is probably around 10.

None of the Mobil GF-5 synthetic oils has a higher HTHS than the 10W30 from what I researched. They certainly have a lower density.

As you can see MS1000 has some pretty solid numbers. 3.2 HTHS is more than adequate for most vehicles that aren't tracked. No, it’s not an extended drain oil but to me that’s a good thing - less is more. What it does have is good shear stability, volitility, and better solubility/polararity than some of its synthetic counterparts. Synthetics and its low density makes you wonder how close to the "W" minimum KV the base oil is and how much is being proped up with VI's. With that, why the selective disclosure on their spec sheets? The Spokian eyebrow has been raised.

 

[Garak]

Your Yaris permits 10w-30 SN/GF-5?

 

[ndfergy]

Originally Posted By: Garak
Your Yaris permits 10w-30 SN/GF-5?


Better than that, the dealership put it in for me. The car is spec'd for both but in the owners' manual 5W30 is recommended where 10W30 is, "OK to use in an emergency but should be replaced with 5W30 on your next oil change". Apparently this is a CAFE thing to prevent ambiguity. Back in late 2015 I purchased snow tires and rims from the dealership and made an appointment to have them installed. I decided to add an oil change with synthetic to the mix. At appointment time during the preliminaries I asked the rep what brand of synthetic they use. TGMO 0W20 was the reply. I told him my car is spec'd for 5W30 so put that in instead. His reply was they only carry the 0W20 in synthetic but it should be fine. Not happy with this and by chance I told him I have a 5L jug of 10W30 synthetic in my trunk so could they use that instead. They agreed and re-worked the charge to a standard oil change less $10.00 for my own oil.

The moral of all this is dealerships are not as altruistic as one thinks - they're there to make money.

 

[Shata]

My personal opinion is use quality oil that your car manufacturer calls for in full syn put good filter on it like fram XG series, royal purple or amsoil and call it a day. The days of oil being like slushy because it's 0F are over these full syns flow just fine. My 2cents. Look at flow tests of full syn oils at -30F on you tube these oils like pennz and mobile 1 are pretty amazing.

 

[veryHeavy]

IN THE CASE OF AMSOIL Signature Series, the 5W-30 is about 2 dollars cheaper than the 0W-30. The same might be true of other brands 5W30 vs. 0W30

I'm curious why people say Mobil 10W30 is less "stout" than 5W30.... I see the 10W has +4 degrees higher flashpoint, which is good for hot CA deserts.

I would think there's a greater difference between Regular M1 and Extended Performance M1 than any two thicknesses.

 

[Garak]

Originally Posted By: ndfergy
Better than that, the dealership put it in for me.

So, basically, the dealership did what was convenient for them, and paid lip service to the specifications. I don't know about dealers sometimes, or shops in general. It's not like Imperial Oil charges more for 10w-30 over 5w-30 in their PCMO lines.

Note that my G37 doesn't require 5w-30 SM/GF-4 or better. It calls for SM or better in 5w-30, with GF-4 or newer being optional. So, there are real enhanced HTHS options available, rather than wiggling an extra 0.1 in HTHS from an ILSAC 10w-30.

If your vehicle is speced for the 0w-20 in the first place, I can't see 5w-30 being much of a concern. If ILSAC wasn't a problem, you could go to Imperial Oil and get Delvac 1 LE 5w-30 in SN.

veryHeavy: The example in the paragraph above, the Delvac 1 LE 5w-30, is more stout than either M1 ILSAC 30, and at a significantly cheaper price up here.

 

[veryHeavy]

Wow didn't know Mobil Delvac 1 now has a xW-30 grade. It was always 5W-40. Thank you for the info :-D