That is an Australian service bulletin for Isuzus sold here rebadged as "Holden" Rodeos (pick ups) and Jackaroos (Troopers).
The RA/RB series goes from 1997 - 2003 IIRC.
Most of those engines (6VD1) are a single overhead cam model putting out about 190 HP.
But the oil consumption figures would still be relevant to the US engines.
PK