Any real drawback to SM / advantage to SN (PP)

[mark pruett]

About 2-3 months ago, I got a 5 qt jug of Pennzoil Platinum from Wal-Mart, and I was kind of lazy, and didn't check the API rating, under the thinking that May was plenty late to not see SM rated oil.

Unfortunately, I assumed wrong, and ended up with a jug of SM rated oil.

Is there any real advantage to SN rated Pennzoil Platinum worth exchanging the jug?

 

[daves87rs]

Nope...heck, I've picked up some SM flavored oils (like QS) on sale!


You're good to go!

 

[Astro14]

What are you putting it in? What does it require?

My point: if your car requires SM or earlier...then, you're good...

 

[addyguy]

There's actually not THAT much difference between SM and SN oils.

Maximun additive levels are the same, NOAK maximums are the same...if you look at a VOA, the two oils look almost identical.

I think the 'new specification' and resulting 'certifying fees' were a tiny bit of a cash grab by the API....

 

[Patman]

My gut feeling says that a lot of the top quality synthetics like PP were already built good enough to pass SN even in their SM formula, so there could very well be a lot of oils on the market right now which are unchanged from SM to SN.

 

[Patman]

Originally Posted By: Astro14


My point: if your car requires SM or earlier...then, you're good...


Are there any cars sold yet which say in the manual that they need SN oil? I think that when a new API spec comes out the car makers wait a little while before putting it as a requirement in the owner's manuals since they know a lot of places (like their own dealer network for instance) will still have a huge stock pile of the previous API spec oil leftover.

 

[Artem]

Nothing wrong with the SM lube. I wouldn't spend the time and effort going and exchanging it.

What will you say to the cashier anyway? "ummm, this oil is expired by API standards, i'd like to get the freshest oil possible, please"

 

[daves87rs]

Originally Posted By: Artem
Nothing wrong with the SM lube. I wouldn't spend the time and effort going and exchanging it.

What will you say to the cashier anyway? "ummm, this oil is expired by API standards, i'd like to get the freshest oil possible, please"

Lol...

 

[mongo161]

Even the Generic Store Brand Synthetic oils in API-SM, GF-4, meet or exceed the requirements.

PP in SM bought a few months ago is all you need....plus you most likely got it for less than what it sells for today!

 

[A_Harman]

SN specifications have a couple of advantages over SM; phosphorous retention, and E85 tolerance. If you don't run E85 fuel, the latter benefit is moot. The phos retention spec I think is a worthwhile benefit, but if your engine is spec'ed for SM, use it without worry.

 

[ahoier]

I don't see a problem.....If I recall, is was Pennzoil themselves marketing their "SM" oils as "meeting latest API specs" before the new API specs were even out/active/enforced/mandated/whatever-ya-wanna-call-it.....

Use it without any problems. If you go return it, you're more likely to get a drained and refilled bottle of used oil, than you are blowing your motor using this "SM" oil

 

[SS1970chrysler]

My cars use SE or SF so just about anything I find is good.

Currently, I'm using some old SL stock.

 

[mechtech2]

All sorts of things are improved with the SN oils. [In a minor amount.] If I grab a jug, I will always want the newest.

But unless you have special needs, the older SM is going to be undiscernable in real life.

 

[CATERHAM]

If you really want to know what you're buying it's best to check the PDS info' on the SM and SN versions of the oil.
You just can't assume the SN formulation is automatically better.

For example, Castrol Edge made a dramatic change in the formulation of their 0W-20 and 5W-20 oils with the move from SM to SN. The VI of their 0W-20 dropped from and industry high of 220 to an industry low of 161 for that grade. The end result is an oil 25% heavier at room temperature and almost 40% heavier at 0C.
That's something I'd want to know if I was aleady running the SM Edge and was happy with the oil's viscosity. A change in oil brand would likely be in order.

 

[buster]

Yeah but you're just focusing on VI. If you look at the Lubrizol spider diagram, SN is superior in every way or equal to SM. People are funny when it comes to oil. They somehow think quality goes down per API upgrade, and yet engines and oils have never been better. And the data supports this without question. The general public has absolutely no clue about motor oil. These people are probably worrying about something more meaningful. LOL

 

[widman]

There is a big difference, specially in certain types of driving.. Other than base requirements, the new detergents are better at fighting sludge, the phos retention (although one change won;t make a big deal).

 

[buster]

The most drastic change was the turbo/deposit and oxidation changes. Wear remained the same.

 

[mongo161]

There are also changes to the add packs between the SM and SN oils. Some add packs were very robust, on paper, with their API-SM, GF-4 rating. When they came out with the new API-SN, GF-5 categories, the add packs on paper, per VOA, showed the lowering or removal of anti-wear and detergent ingredients and replacing them with so called, "Organic" ingredients.

Case in point.....Valvoline MaxLife HM, Red Jug, changed it's label from Synthetic blend to just plain MaxLife. They took the Moly out and reduced the Boron and substituted it with Sodium...or an Organic ingredient that does not show up on a VOA.

Another oil, that was held in high esteem, Texaco, Havoline with Deposit Shield has removed the Moly. It is now Chevron Havoline with Deposit Shield.

Pennzoil Conventional in their newer formulation of SN, GF-5 added a real robust shot of Moly to their oil from the previous version of SM, GF-4

So it's all up to the end user to see what changes have been made and if they are to your liking.

BTW....I've still got some jugs of 5 quarts of Golden Castrol Edge, SM, GF-4 that exceed the GF-5 requirements in my stash.

Cheers.

 

[mark pruett]

Originally Posted By: Artem
What will you say to the cashier anyway? "ummm, this oil is expired by API standards, i'd like to get the freshest oil possible, please"

I got it from Wal-Mart; fortunately, you don't even have to justify your return or exchange with them. If it's unopened and obviously from Wal-Mart (my label has their logo on it), they'll exchange it no questions asked.

After reading the thread, I'm just going to use it anyway; I figure if SM rated Pennzoil Conventional 5w30 was good for 6000 miles in my pickup (05 dodge dakota 3.7l v6), then SM rated PP should certainly be good for 8k.

 

[CATERHAM]

Originally Posted By: buster
Yeah but you're just focusing on VI. If you look at the Lubrizol spider diagram, SN is superior in every way or equal to SM.

Viscosity is the single most important attribute of a motor oil.

No argument that the SN standard is higher or equal to SM.
My point is that a formulator may not be successful in meeting the new standard without making unacceptable compromises.