Well upon close inspection of cases of Delo 400, 2 cases are the CI4+ and one case is the CI-4. Looks like the CI4 is stamped with a 2003 year and the CI4+ has a 2006 year. Will the older CI4 be a good oil in my 94 Cummins? I was under the impression all 3 cases were the CI4+. Thanks for your help, Ken