I was wondering if somebody could 'school' me on the different groups of oils. This thread was inspired by Tallpaul's post in the "change to synthetic" thread, though I've wondered for quite some time.

What's a group I, II, III, IV, V, etc oil? I think it maybe has to do with the base stock of the oil? It appears the further up, the better performance. Would Group I be Dino, II be quality dino/mild synthetic, III be Good Synthetic, IV be great, and so on. Something like that, I am just curious. I know all about the blood of my body, so why not about the lifeblood of my truck? =)

 

Saurian, I would invite you to visit the Chevron library. The Chevron library is the most unbiased information on the internet in regards to the oil groups, additive packages, and pros and cons of each type of basestock. Some of it will be slightly dated so look for the date on the article. WARNING!!!!!! Their site can be very habit forming if you have the desire to become educated concerning lubricating fluids. To give you an answer here and give you a complete answer would require far to much info. It is simple yet complex. Just telling you that Gp I is solvent refined is an incomplete answer. The hows and whys are what makes it interesting. Also, you may find the history behind Chevron interesting. Just do a search for Chevron and enjoy the ride- it's a long one.

 

I agree Chevron is a good site for information .

Here is one I had bookmarked worth cruising through as well plus Lubrizol and www.hatcocorporation.com has alot of info .

http://www.kittiwake.com/knowledge_b.../articles5.asp

Googling information without Amsoil coming up is an art of sorts

I always search like

Polyalphaolefin + engine oil - Amsoil

 

Just a quick note about group I base oils and their inherent solvency .

The high levels of Ca and Mg in HDD oils are a reflection of both the high level of detergency and the TBN. The high TBN is established by "over basing" the organic acid detergents. This is accomplished by adding excess Ca and/or Mg hydroxide to the detergent package. This allows the additive package in HDD oils to neutralize acids for a longer time than PCMOs. The limit for addition of over-based detergent is solvency. Add too much and the additives will drop out of solution.

That was sent to me by an internet aquaintence so it was easier to paste it than to write so.......

When you see the MSDS's showing group I is still used that's not all bad . Mobil's 1300S is about 20% groupI still the aid in prevention of additive pack drop out however the lower wt passenger cars oils have more than ample additives to run the recommended intervals these days .

For the most part and rule of thumb, the better the base oil the lesser the additive pack has to be . Look at the Rotella 5w-40 . It looks weak in the knee but does fairly well for the price .

Phillips Trop Artic 5w-30 looks really low in additives yet does very well at 3-4k drains with it's group II base oil .

Then there are the killer oils like Synergyn and others........best base oils available and loaded with ashless type additives that might add to the confusion and seem to be a weak base oil since it has alot of additves .

Then of course there are weak base oil used with cheap , weak additives in some bottled oils . Buyer...beware

They are all built a bit different and deliver similar performance to an extent yet we as oil nuts look for perfection .

 

Even coming here to FTE seems to be challenging in that regard on some days.

Thanks guys..I'll keep reading. I take it there's no straight answer on the group's, etc lol.

 

Saurian, here's a link to some research I did on base oil groups a while back. A lot of the info came from the Chevron library. Base Oil Technology

Group I - Solvent refined petroleum base stock.

Group II - Hydroisomerized petroleum base stock. Viscosity Index 80-119.

Group II+ - Hydroisomerized petroleum base stock. Viscosity Index 110-119.

Group III - Hydroisomerized petroleum base stock. Viscosity index >120. This gets to be labled "synthetic".

Group IV - PAO based synthetic.

Group V - Ester based synthetic.

 

So Group I is bad because with its low viscosity, it would require killer amounts of VM's to make it good. Group II would be a good dino, Group II+ synthetic blend (to get such good levels), Group III would be a good synthetic, Group IV and V are really good synthetics..and from my reading, the Ester-based ones are the best due to uniform molecular structure and naturally high viscosity and resistances?

Group I = Generic Orielly's crap?
Group II = Motorcraft
Group II+ = Valvoline Durablend
Group III = Mobil 1
Group IV = Redline Synthetics
Group V = ???

This may be overly simplistic...but its the way I'm interpreting things. Also..what would be an example of a Group V? If you ran a Group V lubricant from after your rings seated, you would pretty much never have to worry about your engine grenading itself. Great film protection, thermal resistances, all that good stuff that Ester's pack.

EDIT: I was reading a website I googled, and it stated that Group V base stock is used in formulation of additive packages as opposed to the actual formulation of an oil. Ironically, this came off of a website that as it went down, began asking if you wanted to become an Amsoil dealer. Just can't get away from them!

 

Group III = Valvoline Syntec
Group IV = Mobil1
Group V = Redline

 

Isn't Syntec a Castrol product, and the Valvoline called Synpower?

So I was a level off on my products, ok! I'm starting to catch it a bit. So basically a Group II oil is the good Dino that we all love, and Group II+ and beyond are the happy blends and full synthetics you don't have to worry about. Does it say what "group" the base stock is derived from on the bottle of oil?

 

Valvoline Maxlife, all grades, according to the Material Safety Data Sheets (MSDS) is mostly Group I with roughly 15% PAO (Group IV). Performs quite well.

Looking at the Valvoline Durablend MSDS, it appears 5w20 and 5w30 are mostly group II, II+, and III, with a small amount of group I. But the 10w30 and 15w40 Durablend are mostly group I and the 10w40 shows no group I, just a lot of group II, II+ and/or III.

Confusing? Here's more, MSDS for Vavloline Synpower shows group III for all grades, but .... the MSDS for 20w50 Synpower indicates PAO (group IV).

 

Some refiners have demonstrated advanced solvent refining techniques that result in Group I oils with VIs higher than Group IIs. I don't think that they are being marketed yet, but soon.

Also, to meet the new SM gasser spec, there is a Group II+. I forget the features of that base oil.

I don't think that you can really base your opinion solely on Group # any more.

Any SM-rated oil is going to be a very, very good oil. You can run something more expensive, but it is unlikely that you will see any real benefit.

Sorry if this offends anyone. But I (and members of my family) have been running cheapo, generic (but properly graded) oil for decades with no problems what so ever.

If it makes you feel better to run a brand name, watch for sales and stock up. I bought Shell and Exxon for $0.59/qt., PZ for $0.89/qt.

 

There is also a new group 6 that the new Shell EOP synthetic base oil will fall under as I understand .

Been waiting for this base oil that is supposed to cost far less to make than PAO and actually outperform it too . Time will tell

 

And the extremely low Noack seems to back it up .

 

Hey, the 10w30 Synpower has the same low NAOACK (8) but is Gp III. All the other synpower is NOACK 11. Glad my free synpower is the 10w30. Gonna try it in the Aerostar which is using a quart of Maxlife 10w30 in 1500 miles.

 

Those 30wt Synpower's have PAO too . It's a blend of PAO/Group III .

Obviously the 10w-30 has more PAO and I think it is about 40percent if I remember correctly .

Castrol Syntec is not group III only either .

Some on the market are all group III though . Maxlife Synthetic is one of them .

BTW , about the post and better group I's . They are group I+ and Citgo uses them and certainly others do . Difficult to find out that type info though .