Hey guys i am an american living in the Philippines and i have a 01 hilux 4door mine has a 2.8L diesel a 151f tranny and a 23spline geardrive transfercase that is all factory equpiment  so but my friend in Queensland, AU has the same truck accept for it being a right hand drive and it has the taco transfercase both of them are built within 1 month of each other mine being the newer of the two.. so it is my guess that the older stuff and the newer stuff are still being mixed mine has a 8inch rear and had a 7.5 ifs in the front before i did a sas on it with nissan patrol 13_ ??mm high pinion( this nissan is the same axle housing  found in the 80 - 100 series Land Cruiser but the spline counts are different on the axles but r&p inter change even though the third member looks a little different mesure ments are all the same +/- .008)  the truck did have factory 4.88 gears that was a plus i am planning put tirple cases in it there is some great wheeling in the philippines... volcanoes are really cool to wheel on but the ash is like quicksand... get it out quick or you will loose it for ever