DD, what is the difference between CI-4 and CI-4plus? Many forum members believe that Delvac 1 and Mobil T&SUV are the same oils. When I look at their specs, everything look the same except their API rating. Delvac is rated CI-4 plus whereas T&SUV is rated only CI-4. Delvac also has ACEA rating of E5.
m.
m, the E5 rating is not relevant to our cars. E5 is strictly a truck standard. B3 and B4 are relevant under ACEA standards.
Mobil labeling: It may be they have not gotten around to updating all the data sheets. Both D1 and the T&SUV product fully meet the requirements of the VEP engine...no concerns there. I know Mobil alludes to the fact the oils are not 100% identical and won't reveal what those subtle differences might be. I wouldn't get hung up on it. If it really does bother someone, spend the extra $$ and purchase the D1.
Here's what I've heard about CI4 vs. CI4 plus:
EGR (cooled) was introduced on heavy trucks back in 2002. The soot loading and build up of acidic gases has been taking its toll and the CI4 oil hasn't been getting the job done. As we all know, protection of the upper-most ring is critical and the fleet operators are reporting problems. The new oil, CI4+, is supposed to offer longer drain intervals, improved soot handling and better overall protection. Viscosity control (excessive thickening, filter clogging) has been another complaint, the oil is breaking down too early and the promised extended drain intervals are not materializing. The industry is not happy about this and driving their maintenance costs up. The CI4+ is supposed to have superior shear stability...that will be one major selling point.
The overall "life cycle" of the CI4 oils (introduced about 2 years) ago has been too short for the trucking industry and that's a group
VERY focused on containing costs....for obvious reasons.
People are saying the CI4+ oil is what the CI4 oils
should have been when introduced a few years ago. API is now in catch-up mode with the release of this modified standard. This is a nice working example of why the "latest and greatest" isn't always.
IMO, these issues are not terribly relevant to our modest TDi engines. Look at any recent oil analysis and you'll see how low the soot is and the viscosity not far from new oil. The TDi is a very "clean" engine compared to these trucks.
HTH