Hi guys. I have 2 mid-size diesel SUVs (common rail engines, Asian models) and they specify use of API CF-rated oils. What benefits do I get, if any, by using a higher rated oil (e.g. CI-4) with the same grade?
Another related question. I've been using Mobil Delvac MX (dino) CI-4 rated oil for the last 2 years on these 2 diesel SUVs and I follow OEM OCI. I found 2 sealed bottles of Shell Helix PCMO (API SM/CF rated) in my storage area, left over from my previous Honda CR-V which I already sold about 2 years ago. I was thinking of using this Shell oil in one of the SUVs rather than give it away. You think its fine to use it on the diesels?
Another related question. I've been using Mobil Delvac MX (dino) CI-4 rated oil for the last 2 years on these 2 diesel SUVs and I follow OEM OCI. I found 2 sealed bottles of Shell Helix PCMO (API SM/CF rated) in my storage area, left over from my previous Honda CR-V which I already sold about 2 years ago. I was thinking of using this Shell oil in one of the SUVs rather than give it away. You think its fine to use it on the diesels?