I don't think there is much consistancy in this.
My 3.2L VX uses absolutely no oil between oil changes.

My mate's 3.2L Jackaroo (I think Trooper in USA) just blew a motor because of low oil level.
It has used oil for the past 3 years he has owned it, but just got overlooked once too often. He is going to try a repower with the 3.8L Commodore motor.
That will be interesting to see.

PK