Castrol 10w-30 vs Mobil 15w-40

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Sep 5, 2005
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western australia
Hi

Been a long since last post

Help choose an oil between the Castrol Magnatec Stop-Start 10W-30 or Mobil Super™ Everyday Protection 15W-40 below.

Vehicle Holden commodore 3800 V6.
Over 250000 kms
City driving, trips vary between 10 t0 20km trips
Climate 3 to 25 deg C winter

I am leaning towards the Castrol 10w-30 as the 100 deg CP is 12.4 and it is rated SN and A3/B4.
It almost a thin 40 wt,

Any advantage of 15w-40.

See oil specs below


Castrol Magnatec Stop-Start 10W-30
Typical Characteristics
Name Method Units Castrol Magnatec Stop-Start 10W-30
Density @ 15C, Relative ASTM D4052 g/ml 0.869
Viscosity, Kinematic 100C ASTM D445 mm²/s 12.4
Viscosity, CCS -25C (10W) ASTM D5293 mPa.s (cP) 6640
Viscosity, Kinematic 40°C cSt ASTM D445 cSt 84
Viscosity Index ASTM D2270 None 142
Pour Point ASTM D97 °C -39
Flash Point, PMCC ASTM D93 °C 202.5
Ash, Sulphated ASTM D874 % wt 1.22
Product Performance Claims
ACEA A3/B3, A3/B4
API SN

OR

Mobil Super™ Everyday Protection 15W-40

This product has the following approvals: MB-Approval 229.1 VW 501 01 VW 505 00

This product meets or exceeds the requirements of: API SJ API SL API SM API SN API SN PLUS ACEA A3/B3

Properties and Specifications

Property
GradeSAE 15W-40
Density @ 15.6 C, g/ml, ASTM D40520.873
Total Base Number, mgKOH/g, ASTM D28969.9
Viscosity Index, ASTM D2270143
Kinematic Viscosity @ 40 C, mm2/s, ASTM D445104
Hi-Temp Hi-Shear Viscosity @ 150 C 1x10(6) sec(-1), mPa.s, ASTM D46833.9
Mini-Rotary Viscometer, Apparent Viscosity, -25 C, mPa.s, ASTM D468414600
Pour Point, °C, ASTM D97-39
Ash, Sulfated, mass%, ASTM D8740.9
Flash Point, Cleveland Open Cup, °C, ASTM D92239
Kinematic Viscosity @ 100 C, mm2/s, ASTM D44514.5
 
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Melbourne, Australia
I had a 2004 Commodore myself - I used to use 10w40 (Nulon) in the colder months and 10w50 (penrite) in the warmer months.

In hindsight I wouldn't go thicker than 10w40

I think it was quieter on the thicker stuff - Between your choices and given the kms, go with the mobil 15w40

(Though do recommend the 10w40 Nulon 'Fast Flow' especially when on sale) - Picked up 5L for $28 recently
 
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Looks like I have to be that guy...
What does the manual say about engine oil specifications? Any oil consumption between services?
 

virginoil

Thread starter
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western australia
The OEM Manual states 10w-30.

The owners manual states the following which is the same note I have extracted from Mobil's lube match site for ease of cut and paste

Note
If MOBIL SUPER 1000 10W-30 * is unavailable, use MOBIL SPECIAL 20W-50 * or MOBIL SUPER 1000 20W-50 for normal driving, or MOBIL SUPER 1000 X2 15W-40, MOBIL SUPER 1000 DIESEL 15W-40, MOBIL DELVAC MODERN 15W-40 FULL PROTECTION * or MOBIL DELVAC MX ESP 15W-40 for prolonged use in cold (snow) areas. With LPG engine, use MOBIL DELVAC MODERN 15W-40 FULL PROTECTION *, MOBIL DELVAC MX ESP 15W-40 or MOBIL SUPER 1000 DIESEL 15W-40 meeting Spec. No HN2314.
 
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I don’t see the reasoning behind jumping from a 30 grade to a 50 grade.
 
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That 15w-40 is thick enough for the engine. Australia is a pretty warm place in all seasons.
 
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I live in Texas. My Isuzu p/up takes those viscosities, but I'll take the 15w-40. Australia is in for a winter months so take the 10w-30
 

SR5

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I've used the semi-synthetic Castrol Magnatec 10W30 (API SN & ACEA A3/B4) before, I found it very smooth running. If it's at a good price, then I would grab it.
 
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Severe condition (extreme hot weather, pickup etc..) use the 15w40 grade. Otherwise use 10w30.
 
Joined
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Aitkin,MN,USA
I had a 2004 Commodore myself - I used to use 10w40 (Nulon) in the colder months and 10w50 (penrite) in the warmer months.

In hindsight I wouldn't go thicker than 10w40

I think it was quieter on the thicker stuff - Between your choices and given the kms, go with the mobil 15w40

(Though do recommend the 10w40 Nulon 'Fast Flow' especially when on sale) - Picked up 5L for $28 recently
I've used the semi-synthetic Castrol Magnatec 10W30 (API SN & ACEA A3/B4) before, I found it very smooth running. If it's at a good price, then I would grab it.
Severe condition (extreme hot weather, pickup etc..) use the 15w40 grade. Otherwise use 10w30.
I don't get it. I would never run hot heavier than owners manual. Like never 40 when mfgr says 30.. except a guy here says he can hear pin noise !?!? If I was in Iraq .I would run what warranty/manual says. That said I think all mfgrs(engineers) have sent out bulletins recommending using 0W instead of formerly specified 5w. No I don't have lab report tested fleet used oil. How many here assure there new filters are installed wet and all your zerks get greased? My dad got 500000miles..1953 BuickSuperV8 w/Dynaflow. But lost the original differential at 130000..he never changed rear end lube. That was awake up call. He ran Shell 10w30 burned 1qt at 3000. ..then he'd change oil and filter and lube zerks anyway. Oh.. the Nailhead had one fussy lifter that would quietly click if it did not get a drink of CD2 every 18000? Miles.
 
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I don't get it. I would never run hot heavier than owners manual. Like never 40 when mfgr says 30.. except a guy here says he can hear pin noise !?!? If I was in Iraq .I would run what warranty/manual says. That said I think all mfgrs(engineers) have sent out bulletins recommending using 0W instead of formerly specified 5w. No I don't have lab report tested fleet used oil. How many here assure there new filters are installed wet and all your zerks get greased? My dad got 500000miles..1953 BuickSuperV8 w/Dynaflow. But lost the original differential at 130000..he never changed rear end lube. That was awake up call. He ran Shell 10w30 burned 1qt at 3000. ..then he'd change oil and filter and lube zerks anyway. Oh.. the Nailhead had one fussy lifter that would quietly click if it did not get a drink of CD2 every 18000? Miles.
Please try and make a technically cogent response.
 
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