What Oil Grades are Best for My DD 6V92?

[Dick Quirk]

I need to make sure that I understand your guidance here. I have a '78 with a Detroit 6V92TA. The engine was produce in 1980, and retrofitted to the coach. In all that I have read, especially from Detroit, the only oil to use under standard conditions is SAE 40 oil. Detroit does especially speak strongly against multi viscosity oils. If I understand you correctly, Delvac is the unique exception to this rule. With an engine of this model and age, should I switch to Delvac 1?

Last question...what about the other Delvac's, are they also appropriate, or is Delvac I the only Delvac to use in these engines?


Dick Quirk

[TechTalk]

There is a lot of confusion about this subject. However, although many Detroit Diesel service techs are not aware of this exception to their general rules, the short answer is that multi-vis Delvac 1 oil performs very well in Detroit Diesel 92 series engines. If you are not comfortable using multi-vis oil, you should consider using Detroit's private label SAE40 synthetic, available through Detroit distributors.