When I looked up the MSDS for Delo 400 15W-40 (CI-4 rating) in the Asia Pacific region, it is listed as majority Group I, with 10% or less Group II.
Chevron MSDS … search Delo (listings 321 -340).
The Delo 400 LE 15W-40 only lists "highly refined mineral oil" … which likely means Group II. It is CJ-4 rated (the Delo Gold (ISOSYN) 15W-40 is also listed as "highly refined mineral oil" and ISOSYN = Group II.)
Generally, the CI-4 15W-40's outside North America are going to mostly Group I based. The CI-4+ rated 15W-40 … not sure. These may require a good dose of Group II to get the + rating.
The CJ-4 15W-40's look like they may be all Group II even outside of NA.
Might check out Pennzoil Longlife Gold 15W-40 (it's CJ-4) which is very likely a Group II based oil.
THE alternative would be a reasonably priced Group III based synthetic 5W-40 like Mobil 3000 X2 and running longer drains.
Would it still be worth running either with gp1 still in it ?
Not in my view. There is a huge difference in oxidative stability between GI and GII ( ~ 3x). The aromatics in GI's just can't take the heat well at all.
I'd run a more expensive Group III synthetic at longer intervals to offset the cost if no GII oils were available. Typically, you can run synthetics 3-4x the interval of a GI based oil, GII in the 2-3x range of GI.
vxcalais - You asked:
"Are all CI-4 or CI-4+ oils with a SL rating semi Synthetic such as Delo 400 or Delvac MX Multi grade? Can they still be made using Group 1 ?"
IME the answers are:
No and, yes!
Commercial HDEOs are different "animals" than PCMOs as you already know. They perform their tasks very well indeed according to their specifications and in their intended applications - and when used as directed! Brands matter very little except at the highest end and in specialised applications
So a CI-4+ can be synthetic or a mineral oil, correct? We are using Service Pro Heavy Duty CI-4+ 15W-40 and in the catalog we order from, they have a heading for synthetic and semi-synthetic and the CI-4+ is not listed under either catagory. Also, looking at product info I notice that the Service Pro we're using has a much higher pour point than other oils that are specifically listed as synthetic. Usually as much as 20 or 30 deg. higher. I'm using some Auto-Rx in my truck and am hoping to use the oil we have on hand but I know they advise against using synthetics with the A-Rx.