Trimatic 3-speed automatic (from late HK/HT) Powerglide on earliest HK
Castrol Transmax Dexron III / Penrite Dex III
Trimatic dry-fill figure of ~7 L (converter + pan) is forum-sourced from Holden factory Trimatic diagnosis literature for the HQ generation a simple drain-and-refill from the pan takes considerably less (~3-4 L). Verify against a factory manual for the exact model.
Six-cylinder capacity is a typical figure for this Red-motor family Radial Tuned Suspension (RTS) introduced drivetrain oils unchanged from HX. Verify exact figure for the specific engine capacity fitted against a factory manual.