If a diesel engine is equipped with a diesel particulate filter (DPF) which of the following lube oil classifications must NOT be used?
A) FA-4
B) CK-4
C) CJ-4
D) GI-4

Question

Quizplus · Accepted Answer

GI-4 is not a recognized API service category for diesel engines. The correct categories for modern diesel engines, especially those equipped with DPFs, are CJ-4, CK-4, and FA-4. These classifications ensure the oil is compatible with the emissions control systems and will not damage the DPF.

If a Diesel Engine Is Equipped with a Diesel Particulate