Reasons you Prefer 10W30 Synthetic Oil ?

[LowMilesLesabre]

I used to run 5w30 in my older vehicles

I noticed the same thing in my 99 Buick’s 3800 V6. This particular engine is much happier (quieter and no slap) with 10W-30 and I live in southern Ontario but it’s not an issue as I simply plug in my pan warmer on the very cold nights.

 

[LowMilesLesabre]

I tend to fall on the "thin oil" side although I'm both really. I think 10W-30 still has a place especially in higher mileage applications. I think the last car that actually called for it was the Chrysler/Dodge 3.5 HO? I know a lot of GM 3800's called for it in the 2000's after initially recommending 5W-30 in the earlier LeSabres and Bonnivilles.

That’s very interesting. At all the auto parts stores in my area, virtually all 10W30, no matter which brand, are synthetic blends. For example, the Castrol GTX 10W30 high mileage and non-high mileage oils are all synthetic blends.
But even here the 5W-30's are nearly all listed as synblends and can easily be used in the above applications whereas a 10W-30 can still be a "conventional". Though I am guessing they still contain some Group III at least..

 

[ARCOgraphite]

I still think it is a useful grade in the summer; a little thicker base oil, a little less VII, a little lower NOACK can’t be a bad thing in the heat of summer.

With the stuff I am using it is a ton less VM** - at least according to GOKHANS spreadsheet
It reports at 2 of AMS SIG 5w30 (5.2%) and/or M1EP 5W30 (7.9%)

QSUD10W30 (2.6%) and again a pour point of -54 degC (ASTM D97)

I originally ran the stuff in my snowblower, and I could easily pull cord start it at 15 or 20 degF.
This made me say to myself "This can go in the diluter FORD" ... and it did
And before you say to yourself " Well I'll just run the QSFS 5W30. Nope. 2x the VM.

-Ken
___________
** I must note that the VI reported in this table for QSUD 10W30 seems high. I don't have the older QSUD document to reference and double check.

 

[Overfill]

The problem is that usually, with the majors, they just reduce the base oil quality instead; make the product cheaper to formulate. Mobil is quite upfront about you being able to blend a 10W-30 with no group III using just their EHC Group II/II+ products, along with a 5w-30 (but you can't do dexos).

Example:
View attachment 107135

85% of the base oil blend is 5cSt EHC Group II+. Drop the HTHS to PCMO levels and you'd use less of the 120 I suspect.

I THINK I have some Yubase examples too, but with the lack of popularity of 10W-30 and it being excluded from dexos, I suspect with the majors that it's kind of the opposite approach to the 0W-40's where they have to use better bases to keep the Noack down and meet the performance specs. They can get away with making the 10W-30 pretty cheaply because it is basically obsolete for PCMO applications.

If a product is marketed to be "Synthetic" and meet a performance of just API SP, won't they have to still use a Group III, IV, or V because they are selling it as a "Synthetic" on the label? (in which case, the cheapest avenue is a Group III base oil, plus some smidge of VII)
Looking at more "generic" products like Supertech synthetic 10w-30.

 

[blupupher]

Why, when there is 0W-40?

So what does 0w-40 do for me over 10w-30?

 

[OVERKILL]

If a product is marketed to be "Synthetic" and meet a performance of just API SP, won't they have to still use a Group III, IV, or V because they are selling it as a "Synthetic" on the label? (in which case, the cheapest avenue is a Group III base oil, plus some smidge of VII)
Looking at more "generic" products like Supertech synthetic 10w-30.

They can use Group II+ with some Group III and call it synthetic (I don't believe there's any actual regulation on how much) to keep the cost down. It's unfortunate there aren't more blending examples kicking around.

 

[DGXR]

I ran 10w30 in the C4 Corvette because it had a lifter tick with the spec'd 5w30. Somehow the slight change in W rating fixed the tick.
My lowest winter temps are 25F, so 10w30 is always an option for the Tacoma in the rare case I can't find 5w30 when I need it. This is indeed rare because I usually keep materials on hand for at least 1 oil service. But it does happen.
The mower calls for straight 30 grade, I give it Rotella T4 15w40 which also goes in the dirt bikes.

 

[53' Stude]

Why, when there is 0W-40?

Because German vehicles with better or more strict specs specify it.

 

[SR5]

I've run both Castrol Magnatec 10W30 semi-synthetic with ACEA A3/B4 and Castrol Edge 10W30 full synthetic with ACEA A5/B5.

It never gets below freezing here, so these two did me fine. The Euro ratings mean as much or more to me than Dexos ratings, so I don't feel I had an inferior oil in my sump.

 

[Hermann]

Been using Maxlife 10w-30 full syn in my OPE for a decade or more. The NOACK # is 6. That is why.

 

[2022tengamliokf]

I've run both Castrol Magnatec 10W30 semi-synthetic with ACEA A3/B4 and Castrol Edge 10W30 full synthetic with ACEA A5/B5.

It never gets below freezing here, so these two did me fine. The Euro ratings mean as much or more to me than Dexos ratings, so I don't feel I had an inferior oil in my sump.

I would think in "boiler oven" Australia 10W-30 acts more like "5W-20" ?? Don't you guys run more like 10W-40/ 15W-40 or 20W50 down there ??

 

[PimTac]

I would think in "boiler oven" Australia 10W-30 acts more like "5W-20" ?? Don't you guys run more like 10W-40/ 15W-40 or 20W50 down there ??

The cooling system takes care of the heat.

 

[kschachn]

The cooling system takes care of the heat.

I still want to know what he’s got against oil magnets.

 

[2022tengamliokf]

I still want to know what he’s got against oil magnets.

Last ones messed up my filter and oil pan

 

[SR5]

Don't you guys run more like 10W-40/ 15W-40 or 20W50 down there ??

Yes we certainly do run a lot of 10W40 and 15W40 PCMO down here. Not much 20W50 now days, but 5W30 and 10W30 is getting more popular.

Check out what the factory owners manual from Toyota allows for their Camry Hybrid, everything from 0W16 to 15W40, including the topic oil of 10W30.

https://bobistheoilguy.com/forums/threads/2018-camry-hybrid-manual.297507/

 

[Electromotive]

The price.
View attachment 107147

What a bargain! Those deals are few and far between.

 

[PimTac]

Last ones messed up my filter and oil pan

 

[BERLIN]

I use AMSOIL SS Synthetic 10W- 30 In my 4WD 1998 Dodge Dakota because the manual says it is preferred to use 10W- 30 In all climates, and the motor runs extremely well on it at 116,500k, sometimes I plow snow from a cold start and synthetic engine oils are always best for that! then using that quality synthetic oil I also only need one oil change per year around April 1st. I don't need to worry so much about bieng too cold or snow for my annual oil change!

 

[kschachn]

I use AMSOIL SS Synthetic 10W- 30 In my 4WD 1998 Dodge Dakota because the manual says it is preferred to use 10W- 30 In all climates, and the motor runs extremely well on it at 116,500k, sometimes I plow snow from a cold start and synthetic engine oils are always best for that! then using that quality synthetic oil I also only need one oil change per year around April 1st. I don't need to worry so much about bieng too cold or snow for my annual oil change!

But in the other hand that oil does not meet the cold cranking and pumpability requirements for an oil with a 5W winter rating or it would be labeled as such.

 

[BERLIN]

But in the other hand that oil does not meet the cold cranking and pumpability requirements for an oil with a 5W winter rating or it would be labeled as such.

Well I thought the post was why do I prefer 10W- 30 Synthetic.

• Its what my service manual calls for. ( I don't want to be smarter than my owners manual like some people do)
• My engine has run great for years and had no starting or oil problems (Well maintained vehicle in all areas)
• - 52° F Pour Point (That seems very robust to me)
• Using my AMSOIL 10W- 30 SS Synthetic I don't worry about oil concerns other then checking the oil level routinely.