list of commodore series and what diff ratios they had
From VN to VS and VT series 1 all BW 78 diffs had 4 spider centers with 28 spline axles, the standard ratio is 3.08:1 for all models, the V8 models had shot peened gears (crown wheel and pinion). In the VP range Holden first introduced the Independent Rear Suspension (IRS).R6/8 models seems to have been fitted with 3.45 ratio LSD units. XD/XF Falcon utes have 25 spline centres with 3.23 ratio where the sedan models have a 2.77 ratio (this would explain why they seem to be slower on the road when they tended to have a lot more power then the equivalent Commodore model). Note of interest.