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My handbook says 5.8l. Usually takes a touch over 5l to get to full mark though
Good question, they revised the capacity during VX production, the VX handbook says 5 litres including filter, when my VX SS had the new VYII pistons fitted back in 2003 they replaced the oil filler tube and dipstick with the revised set up, and changed the capacity to 5.5 litres, I have the part numbers of the revised set up if you need them and a Holden bulletin about the revision. Going back to your original question when my VX SS has been serviced by Holden and an independent shop I have had various quantities for oil used on the receipts varying from 5 litres to 6 litres, I guess it may depend on how well they let it drain before refilling. When they have supposedly put in 5.5 litres if you check it hot after stopping for a few minutes ie during a refuelling it is usually at the full mark or just a tiny bit over, if however you let it sit overnight and check it the next morning the level is usually above the full and just into the first ripple on the dip stick. If I was doing it myself I would let it drain very well and pop in about 5.5 litres, but I don't think 6 litres would do any harm if it was drained well before refilling. I think the later Ls1's were increased slightly again so maybe VY handbooks say 6.2 litres.
Why new pistons?