Can the same procedure be used on the transfer box and haldex as on the partial ATF fluid change? By that, I mean just remove as much as you can by suction and replace it with the same amount of fresh oil? Mines at 85K now and I've never replaced any of those oils so thinking of doing that fairly soon on my next service. I've had it just under 2 1/2 years now, done 20K in it and apart from a major service with all filters when I first bought it as well as brakes and discs including handbrake shoes, I've changed the oil & filter every 12 months and just the oil every 6 months so its had 4 oil changes and 2 oil filters in that time. Next one will be the big service with another fuel/air/cabin filter and a brake fluid flush. I changed the power steering reservoir and fluid just over a year ago as a precation. What oil do I need for the transfer box and haldex? Anything else you can think of?

Transfer Case - Castrol BOT 118 PLUS 75W90, 0.75 litres
Haldex - Statoil SL01-301, 0.65 litres

Check the oil level is correct as it might be wrong to begin with. I did ask how critical the levels are in the diff & transfer case but no one responded. When I did my rear diff & transfer case I put in a bit more as I wanted to be safe. Can't see a little over is going to be an issue & the car wasn't level so I was guessing a bit. Get the level right on the Haldex though & maybe buy the Haldex oil from Volvo, its cheaper there. You can replace one of the filters without removing the unit too.

Thanks. Any idea where I can get these oils from?

as suggested you can get the Haldex oil from Volvo (cheaper than LR). I got my diff & transfer case oil from LR as it was easy. Not cheap though