Mobil Delvac 15W-40 in my '24 GR86

[YZJB]

Lots of cars in Australia, of all types, running around on 15W40. Simply because all the majors make a 15W40 and sell them at a very low price point. You can get Castrol GTX, Shell Helix HX5, Valvoline Engine Armour and many others, all as 15W40 PCMOs. You can run them year round in our climate.

Mostly they were mineral oils rated API SN/CF and ACEA A3/B3, with natural low Noack and good shear stability. HTHS was around 4.0 - 4.1 cP, from the few that published this data.

More recently some have become semi-synthetic, e.g GTX UltraClean 15W40, and some like the Valvoline EngineArmour / DuraBlend have been upgraded to API SP, Euro ACEA A3/B4 and VW 502/505.

I was at a fuel station recently, and a guy in a nice suit and driving a new Audi bought some mineral 15W40, and I watched him pour it into his engine. He must have got a low oil light or something. Probably not the correct oil, but it will work just fine. At least he topped it up. A friend of mine has a Subaru WRX with the boost turned up, his mechanic told him to run a 15W40 HDEO, and that's all he uses.

I know it seems strange to the North American market, but over here, many people use 15W40 without concern. I often use it myself, and my oil stash contains GTX UltraClean 15W40 and Mobil Delvac 15W40 mixed fleet HDEO.

Changed the oil in an FGII Falcon XR6 Turbo ute today, Delvac 15W-40 CI-4/SL went in. One of the quietist Barras I’ve heard with that oil in it. It’s great stuff

 

[TiGeo]

If you want a thicker oil why not a Euro 40 instead of this HD diesel stuff?

 

[TurboZedd-R]

It is insane the M139 uses 0w-20 while my M133 (2015 GLA45) specs xW-40. I would love to see how long these engines last on the 20 viscosity, compared to the M133s.

The lesser 35s run 5w30, or that's what the dealer puts in my wife's. The M139 platform has so many heat exchangers, I see average oil temps of 160-170f, could have something to do with not using a heavier weight.

 

[Slick3914]

Seems like Mobil 1 0W-40 would be ideal.

 

[bluesubie]

How will a difference of 3 cSts have any effect..just saying.

It’s not a difference of 3 cSts .. just saying.

 

[userfriendly]

Delvac 1300 is a GREAT HDEO. Just look at the UOA's from my Scion and Mazda CX-9. I go 15K miles and the oil still has lots of life in it.

Nevertheless it’s not expensive or exotic enough for this crowd.

 

[TiGeo]

Nevertheless it’s not expensive or exotic enough for this crowd.

Actually the BITOG crowd is about Walmart and cheap. QS Euro 5W40 is what I would run here.

 

[userfriendly]

Actually the BITOG crowd is about Walmart and cheap. QS Euro 5W40 is what I would run here.

Do they have it at Walmart?

 

[4WD]

Nevertheless it’s not expensive or exotic enough for this crowd.

Last I knew - it had a Noack below Shelltella and Delo - around 10…
It’s a good semi for a good price …

 

[TiGeo]

Do they have it at Walmart?

Yes...about the only place haha

 

[Plumb Bob]

Last I knew - it had a Noack below Shelltella and Delo - around 10…
It’s a good semi for a good price …

Especially if you buy the pail at Wally for $69.00.

 

[Al]

It sounds like you really aren’t driving this car hard enough to necessitate a 15w40. You are just losing a little bit of horsepower and fuel economy. I still think you would be better off with one of the Euro 5w30s that has a 3.5 HTHS.

Yea, You Patman. Anything with you and me is not "argument" just "discussion" I think driving the way I do and shifting such the next upper gear is engaging at around 2,000 rpm or lower. Its probably worse than driving for "performance". And for summer I see no NEGATIVE difference between it and the 5W-40 Euro which is in my Forester XT..do you??
Take care.

 

[Patman]

Yea, You Patman. Anything with you and me is not "argument" just "discussion" I think driving the way I do and shifting such the next upper gear is engaging at around 2,000 rpm or lower. Its probably worse than driving for "performance". And for summer I see no NEGATIVE difference between it and the 5W-40 Euro which is in my Forester XT..do you??
Take care.

I’m definitely not arguing with you, we’ve been on here together for a long time and I’m just trying to help you my friend! I’m not saying that your choice is going to be detrimental but it’s a good idea to maybe consider trying out a few other oils to get a feel for what works best for your driving habits For the summer a 15w40 would work just as well if not better than a 0w40. But I still think that an oil with a 3.5 HTHS might just be the sweet spot where you get more protection without losing too much horsepower.

 

[userfriendly]

Especially if you buy the pail at Wally for $69.00.

View attachment 226526

Now if you could find a pail of 10w30 for the same price , you’d have a match made in heaven.
I’m not virtuous enough to run thin engine oils, but instead look for reasons to run thick ones. But, for bearing clearances.0025” and under, I think a HTHS in the 3.7-3.8 range is enough. If higher is needed perhaps a better oil cooler would be a preferred route instead of a thicker oil.
I don’t understand the reasoning behind redundant winter grades like 0W and 5W in hot climates.
Auto manufacturers do that because they don’t know where the vehicle is being shipped to, so 5Wxx or 0Wxx is the norm.

 

[ka9mnx]

Do they have it at Walmart?

Not at the moment. Pulled from the shelves. It is available through on-line ordering though.

 

[Plumb Bob]

Now if you could find a pail of 10w30 for the same price

Unlikely.

 

[BMWTurboDzl]

It sounds like you really aren’t driving this car hard enough to necessitate a 15w40. You are just losing a little bit of horsepower and fuel economy. I still think you would be better off with one of the Euro 5w30s that has a 3.5 HTHS.

Remember the higher the grade the more heat the oil generates due to increased friction.

 

[Al]

For the summer a 15w40 would work just as well if not better than a 0w40. But I still think that an oil with a 3.5 HTHS might just be the sweet spot where you get more protection without losing too much horsepower.

Yea. I never would have gone with this 15W for Winter. That was actually on my mind when I bought it. The other thing is that I get 3 oil changes at 5K mile intervals. I kept the 0W-20 in for500 miles then 5W-30 for another 700 miles. at 60Miles when I get the oil changed I will go with a Euro 40 wt.

 

[SR5]

I don’t understand the reasoning behind redundant winter grades like 0W and 5W in hot climates.
Auto manufacturers do that because they don’t know where the vehicle is being shipped to, so 5Wxx or 0Wxx is the norm.

I agree, when it comes to winter ratings I'm a believer in getting all you require, but no more than you need. At least in theory, if they made it. As for the same formulation you would get better shear stability and lower Noack volatility.

I want a M1 10W40 A3/B4 with Porsche A40 & MB 229.5, and a Castrol Edge 10W30 with API SP & Dexos1-Gen3. But you will never get it, as GM, MB and Porsche don't allow these winter ratings as they don't know the climate of their customers. They want their approved oils to work everywhere and every season. I understand, I would probably do the same if I was the boss.

Still HDEOs in 10W30 and 15W40 are as close to it as we come, and I see the OP's point.
BTW when I first joined BITOG about 9 years ago, mixed fleet mineral or synblend HDEOs were a poor man's synthetic and a lot more people were running them back then.

 

[LordNilesStandish]

The Subaru boxers love a thicker oil.
My wife has a 2006 EZ30R. The 3.0 litre H6 with a subaru type of VTec yo. 242 ps.
This isn't a high mile engine and is a complex and tight clearance type.
Currently it's filled with 10W50 for the first time.
It loves it. After driving a few times, so smooth, lost all harshness, lost its lifter tick... runs strong.
I have previously used 10W40 in this engine with great results.
I would never run anything thinner than 40 and I am considering going a 15W40 mixed fleet or similar but have 2 by 6 L bottles of 10W40 to work through first.
Subaru's are a different animal and need thicker oil for best performance and longevity. Many modded WRX/STI owners run 10-20W50-60 just to keep them alive.
15W40 sounds about perfect.