Would there be any problems using Delvac 1 5-40wt engine oil, in a 2002 Dodge 4x4 truck? I planed to use Mobil 1, at the first oil change, but after seeing Bob,s film clip on Mobile 1 and how poor it did. It seemed the Diesel oils did well. Would the higher ash level be a problem? Dodge calls for 10w-30, how far off cauld the 5-40 be?