Havoline DS 10W-30 vs. Straight-30

[addyguy]

Havoline 10w30 DS is a very, very thin 30-weight, being 9.7 cst@100. It has a viscosity index of 134, and a fairly thin 40C viscosity of 65.

Havoline straight-30 weight DS is also thin, being 10.3cst@100C. Its viscosity index is 107, and 40C visc. is 80.

It is well-known that Havoline oils are made using a group II+ base oil from Chevron. By definition, a group II+ base oil has a viscosity index of 120-130. That would mean that 10w30 Havoline uses very, very little VII in it, as it is only just above the 130 VI cut-off for its group II+ base.

What I'm curious about is why the straight-30 Havoline DS, if it uses the same base oil, has such different specs - it has a much lower VI, and is much thicker. Do they only use gorup I base oil in the straight grades?

I just thought that having a 10w30 that is that thin, with that 'versatile' of a base oil, would perhaps negate the need for a straight-weight oil in the line-up - the 10w30 IS almost a straight weight.

What am I missing here?

 

[G-MAN]

Originally Posted By: addyguy
It is well-known that Havoline oils are made using a group II+ base oil from Chevron. By definition, a group II+ base oil has a viscosity index of 120-130.


Uh, no. There really is no such thing as a Group II+. Group II base oils can have a VI of 80 to 119. Group III base oils have to have a VI of >120. The "Group II+" name is used unofficially to denote Group II base oils with a VI of >110.

Havoline straight 30 is probably made with typical Group II. The 10w30 may be made with a mix of Group II and Group II+. 5w30, all Group II+. 5w20, all Group II+.

 

[addyguy]

Thanks for the clarification. Wasn't sure if had those VI numbers right!

With that correction, then even the 10w30 DS has to have a fair amount of VII's and PPD's added to make the spread, so it is not as 'close' to a straight weight as I though it was....

 

[Juhsga]

Hi. I just noticed that Advance Auto has a good deal on Havoline DS and it's about time for me to change my oil out. I have V-MaxLife in my 1.8 Corolla 2002 with 4900 miles so far. I think I may get at least 500 more miles out of it but haven't seen oil deals myself for a while or at least oils I would be interested in. So what do you think?

Here's a link to a Prius with a used oil analysis of Havoline DS
http://priuschat.com/forums/file-library/58505-first-uoa-4k-mi-5w30-havoline-deposit-shield.html
...if I were to get the same results should I purchase a 5W-40 if they have it, instead of 5w30 like I have been using because Havoline DS runs really thin?

 

[Audi Junkie]

There is no Havoline DS 5w-40, that's a synth-only visc.

Oils that are formulated thin tend to be shear-resistant.

 

[Juhsga]

I meant should I use a Havoline DS 10w30 vs a 5w30 b/c it runs thin ....