Mobil 1 0w40 vs. 15W-50

[Falcon_LS]

I’m continuing my search for the ‘best’ synthetic for my application; looking at various offerings of different brands, picking out their best offering and making a list, then making a selection. So far I’ve looked at brands like Castrol Edge, Cofran (French), BP Visco 5000, Pennzoil Platinum, Total and Lexus’ own oil. I find the search function to be rather useful, but there are some things I am unsure of, such as whether or not the formulation of the same brand oils vary in the Middle East as opposed to North America and Europe.

That said, I’m now looking at Mobil’s offerings and there appear to be two choices: Mobil 1 0w40 and 15W-50. I recall there being a 5w30 with a green label, but it doesn’t appear on the importer’s website and I’m being told it’s replaced by the 0W-40 offering. Both look great on paper, but I’m having a hard time eliminating one or the other because of advantages unique to each.

I’ve looked at product information sheets for both oils, and am somewhat leaning towards the 15W-50. Apart from the fact that my engine’s run on 20W-50 most of it’s life, with a brief period of MC 10w30 in between, the 15W-50 seems to be the EP formula and happens to have an extra anti-wear additive, which I reckon my engine (156,250 miles and Auto-RX’d) may benefit from. The other reason is the weight range is just a wee bit shorter: 15W-50 vs. 0W-40. I remember reading here that it’s best to pick the shortest, because those oils have a better ability to maintain their viscosity and service life. Then again, I do not know if such a small difference will matter all that much.

The 0W-40, on the other hand, has a couple of benefits over the 15W-50; better cold starting, ILSAC and ACEA standards alongside API, and better fuel economy. However, it also has the “European Protection Formula” as opposed to EP. What are the differences between the “Protection Formula” and “Extended Protection”? The terminology gets rather confusing. Are they the same thing with a different name? Both products benefit from Supersyn technology, naturally.

Finally, I notice the 0W-40 has a viscosity index of 187 as opposed to 154 with the 15W-50. Can somebody explain in simple English what this translates to? Being a thicker oil, everything else has a higher number with the 15W-50, so this confused me with it being lower.

Any assistance will be very much appreciated. This site has been extremely helpful, thank you!

 

[MillerMan]

what is the oil going in? what are your driving habits?

what happened to the 07 Grand Marquis?

 

[Falcon_LS]

Not sure what you mean by "What is the oil going in?"

But my driving habits are not exactly hard on the truck. Worst case scenario, It's 70% highway and 30% city with an average engine rpm within 3,000-4,000 rpm range. The only time it gets higher is at WOT occasionally.

Edit: Engine sees ambient temperatures in excess of 55 Celsius/131 Fahrenheit

My '07 Grand Marquis was rear ended by a semi in standstill traffic on a major highway, in December 2007. It was a Middle East (GCC) Spec GS Convenience with features such as dual exhaust, LS wheels, cloth 40/20/40 Town Car seats, Premium sound system, etc. It was purchased in June '07, so I only had it for a short while.

 

[MillerMan]

LOL, I figured it was smashed

 

[Falcon_LS]

Yeah, well obviously I wasn't LOL about it after dumping $26,000 of hard earned cash on what ended up as scrap metal.

 

[Bambam]

Originally Posted By: Falcon_LS
Not sure what you mean by "What is the oil going in?"

But my driving habits are not exactly hard on the truck. Worst case scenario, It's 70% highway and 30% city with an average engine rpm within 3,000-4,000 rpm range. The only time it gets higher is at WOT occasionally.

Edit: Engine sees ambient temperatures in excess of 55 Celsius/131 Fahrenheit

My '07 Grand Marquis was rear ended by a semi in standstill traffic on a major highway, in December 2007. It was a Middle East (GCC) Spec GS Convenience with features such as dual exhaust, LS wheels, cloth 40/20/40 Town Car seats, Premium sound system, etc. It was purchased in June '07, so I only had it for a short while.

What brand vehicle and engine size are you looking to get oil for is what we're after.

 

[Falcon_LS]

I completely misinterpreted that as "what oil are you planning to put in the engine?"

So much for being up on 3 hours of sleep. It's a Mitsubishi 3.0L V6 (6G72) in my Montero.

 

[StevieC]

I would use the 15w50 in the 55 degree heat and when it's cooler you could go to the 0w40...

 

[Bambam]

Originally Posted By: Falcon_LS
I completely misinterpreted that as "what oil are you planning to put in the engine?"

So much for being up on 3 hours of sleep. It's a Mitsubishi 3.0L V6 (6G72) in my Montero.

Whats the coldest it gets in Kuwait? I am leaning toward the 15w50 myself.

 

[addyguy]

I'd go with the 0W-40 - much better balanced overall oil. Not that the 15W-50 is a bad oil, but I feel the 0W-40 is better.

 

[FrankN4]

I have used Mobil 1 15W-50 in every vehicle I have owned, my daughter's vehicles and their husband's vehicles. Since 1990, we have around 2,000,000 miles on this oil in many different engine types and sizes. Out temperature's range form -18C in the winter to 35C in the summer. We have never had an engine related problem of any kind, never used oil, leaked oil, or even seeped oil. No engines noises and very smooth running engines. Gas mileage was above EPA estimates in every vehicle.

I have a daily use Chevrolet Cavalier that now has 208,000 miles. I have a Toyota pickup truck that has 300,000+ miles. A daughter had a Ford van that had 170,000+ miles when traded, and a Chrysler van that had 190,000 when traded, and many others.

Mobil 1 15W-50 is a unique oil. It has a great pumping/start/pour viscosity. It has a 100C cSt of 18.1, and a HTHS of 4.5. Heavy enough to give excellent protection and light enough to flow easily to every part of the engine.

Mobil 1 15W-50 has a ZDDP content of 1200. It has moly and boron. It has an excellent detergent package.

I am biased. I think this is the current best oil available. Like I said, it is used in everything. The above Ford and Chrysler engines called for 5W-20. everyone told me I would ruin my daughter's engines. From experience, I knew better. This is a biased opinion but form 19 years and 2,000,000 miles of experience.

You can only compare Viscosity Index between oils of same grade. 5w30 to 5w30, 10w30 to 10w30, etc. The VI tells you how little(or not) viscosity changes with changing temperature. 15W-50 has a spread of 35 starting at 15 and ending at 50. Ow-40 has a spread of 40, starting at 0 and ending at 40. If the 0W-40 is any good at all, it had better have a greater spread/higher VI than the 15W-50.

 

[SubieHo]

Here are some kinematic viscosity values for the oils you're considering, including a couple others for comparison. I've been using an old stash of SH & SJ Mobil 1 15W50 in certain applications for years. In your case, either oil would work just fine.

The older formulations of 15W50 (and all others in the Mobil 1 lineup) had higher viscosity index values. What's noteworthy is that below operating temperature, SJ 15W50 has viscometric properties on par with those of the current SM 5W40 TBD.

Temp.-- 100C--- 40C---- 30C---- 20C---- 10C---- 0C----- -10C-- -20C
0W40SM- 14----- 78----- 118---- 189---- 322---- 590---- 1184-- 2642
5W40SM 14.90-- 100---- 161---- 273---- 502---- 1010--- 2266-- 5795
15W50SJ 18.00-- 120---- 190---- 320---- 579---- 1139--- 2480-- 6097
15W50SM 18.10-- 131---- 213---- 369---- 692---- 1424--- 3270-- 8576

 

[Falcon_LS]

Thank you for all the responses. I suppose 15W-50 is the way forward in my case, although it sounds like a good idea to alternate between the two during summer and winter seasons...I quite like the sound of that.

That being said, I did an oil change today on a friend's 2001 2.2L Camry with Mobil 1 0W-40 and a WIX 51394 filter. It has 50,000 km (31,250 miles) on the clock over 9 years and he barely averages 15,000 km per year now. Prior to that, he averaged 5,000 km (3,000 miles a year) until his office moved location. So he'll only get an oil change more or less every year with Mobil 1 now. I drove the car to get the filter and oil before hand, and drove it afterwards. Wow, what a difference. The engine is much more responsive and suddenly much more quieter.

Originally Posted By: Bambam
Whats the coldest it gets in Kuwait? I am leaning toward the 15w50 myself.


Usually around 0 Celsius or 33 Fahrenheit during winter, but that's rare. Out in the open desert, it gets much colder but my vehicle never really sees that type of climate.

Originally Posted By: FrankN4
I have used Mobil 1 15W-50 in every vehicle I have owned, my daughter's vehicles and their husband's vehicles. Since 1990, we have around 2,000,000 miles on this oil in many different engine types and sizes. Out temperature's range form -18C in the winter to 35C in the summer. We have never had an engine related problem of any kind, never used oil, leaked oil, or even seeped oil. No engines noises and very smooth running engines. Gas mileage was above EPA estimates in every vehicle.

I have a daily use Chevrolet Cavalier that now has 208,000 miles. I have a Toyota pickup truck that has 300,000+ miles. A daughter had a Ford van that had 170,000+ miles when traded, and a Chrysler van that had 190,000 when traded, and many others.

Mobil 1 15W-50 is a unique oil. It has a great pumping/start/pour viscosity. It has a 100C cSt of 18.1, and a HTHS of 4.5. Heavy enough to give excellent protection and light enough to flow easily to every part of the engine.

Mobil 1 15W-50 has a ZDDP content of 1200. It has moly and boron. It has an excellent detergent package.

I am biased. I think this is the current best oil available. Like I said, it is used in everything. The above Ford and Chrysler engines called for 5W-20. everyone told me I would ruin my daughter's engines. From experience, I knew better. This is a biased opinion but form 19 years and 2,000,000 miles of experience.

You can only compare Viscosity Index between oils of same grade. 5w30 to 5w30, 10w30 to 10w30, etc. The VI tells you how little(or not) viscosity changes with changing temperature. 15W-50 has a spread of 35 starting at 15 and ending at 50. Ow-40 has a spread of 40, starting at 0 and ending at 40. If the 0W-40 is any good at all, it had better have a greater spread/higher VI than the 15W-50.


Thank you for sharing your personal experiences with the 15W-50! With the sort of mileage you've used this oil, it has to be really good!

It also makes perfect sense about comparisons between viscosity indexes.

Originally Posted By: SubieHo
Here are some kinematic viscosity values for the oils you're considering, including a couple others for comparison. I've been using an old stash of SH & SJ Mobil 1 15W50 in certain applications for years. In your case, either oil would work just fine.

The older formulations of 15W50 (and all others in the Mobil 1 lineup) had higher viscosity index values. What's noteworthy is that below operating temperature, SJ 15W50 has viscometric properties on par with those of the current SM 5W40 TBD.

Temp.-- 100C--- 40C---- 30C---- 20C---- 10C---- 0C----- -10C-- -20C
0W40SM- 14----- 78----- 118---- 189---- 322---- 590---- 1184-- 2642
5W40SM 14.90-- 100---- 161---- 273---- 502---- 1010--- 2266-- 5795
15W50SJ 18.00-- 120---- 190---- 320---- 579---- 1139--- 2480-- 6097
15W50SM 18.10-- 131---- 213---- 369---- 692---- 1424--- 3270-- 8576


That's an interesting comparison, thank you for sharing! After looking at all the oils I've looked into, I've finally decided to stick with what's outlined here. So during the hotter season, it's 15W-50 for me and 0W-40 during the winter.

 

[Steve S]

What are the coldest temps during winter I would guess 15w syn is good below 15*F