I have been asked about the new oil, and quite honestly, my initial impression was, "If it ain't broke, don't fix it". But truthfully, the CK-4 oil is the latest/ greatest diesel oil standard for the diesel industry,. I really did have to read a lot of background subject matter. And I am in favor of the new cert. But I was also fine with the Schaeffer 9000 5-40 CJ-4, too.
Here is your reality check... They have been using the new formula for the last 2 years, but couldn't actually print it on the label until the certification was complete.
That may sound like putting the cart before the horse, but the largest improvement, in my opinion, is the increased soot saturation point.
That to me means that the oil's can survive longer intervals, because the single most common cause on oil analysis to change oil is soot saturation. Once the oil cannot absorb any more soot, it's time to change.
Understanding the mentality of the common TDI driver, it's actually somewhat of a stretch to get them to hold to a 10,000 mile oil change. If the customer actually were to use oil analysis to judge a proper oil change interval, I think many would simply freak out. I actually think a 12-15,000 interval is not unreasonable if considering the CJ-4 rating and now, the soot saturation point has been raised, I don't think it will make any difference, because the customer won't 'take the chance' that engine damage can happen. The big trucking companies always change oil based on oil analysis. They use the oil to its potential. Even I, myself, tend to stick to a 10,000 mile oil change, only because it's easy to see on the odometer. I don't have to make another log. And few people can do a Schaeffer's oil change cheaper that me!
So, The reason I've not been verbal is it really doesn't matter whether you got the older CJ-4 oil or you can find the bottle with the CK-4 rating. For the last two years, the new formula, with the same old label was in the bottle. Now that the certs have been approved, all new bottles will show the CK-4 rating. There appears to be no difference in pricing.
Btw: To give you an idea how this certification process works, it's a bit ugly. As an example, the transmission oil Schaeffer's has for a well-known Allison transmission, they couldn't even get to the table to talk, UNTIL... they made a 'little payment'... and that's the way it works... sometimes you have to 'grease the skids'. They finally got their approval after 5 years of attempts.
Another little game just about made Schaeffer's quit selling their oil in California. The size of the printing for the oil weight was not to California Standard. Schaeffer's was subject to a fine for not knowing that. I'm not sure if the fine got waived, but the new bottles have the larger print. It's that kind of ignorant stuff big business has to put up with..
If you want to play with the big boys, you have to play the game. It's big money in a lucrative market.