So, it seems that:
Outback with 1.5t axle has 7 leaf pack with axle underslung, which is what mine is.
Outback with 2.0t axle has 8 leaf pack with axle overslung, as per Teabags, BlackDiamond, which also results in 2-3 inches less height (which annoys Tbag no end
).
This is all related to legal hitch height, which Jayco are quite anal about. I found this out way back when I was researching campers, and asked Jayco t'ville about underslinging a std on-road jayco, to which they said they would not do it as it would put the drawbar hitch height beyond the legal limit.
Now, the hitch height on my O/B is near on the upper legal limit of about 420mm above ground.
With a 2.0t axle (assume it is physically larger than a 1.5t) and the extra leaf (all of 6 odd mm), these must combine to put the drawbar over the legal height if it is underslung like mine, and I reckon this is the line that Jayco will push when you ask them about it.
One thing to remember about this whole hitch height thing is that it only talks about "towball" height. Nowhere in any of the literature does it mention or relate to couplings (Tregg, orac etc), so, Teabag, I reckon dig up some info on the legal ball heights and, if they take this line, hit them with the "but I don't have a towball, I have a coupling - the laws only talk about towballs" approach.
Until then, looks like you have 3 inches less than me!!!!
There's a reason why I walk they way I do LOL
Nutto