The diesel is quite reliable, but horrendously under-cooled. Cooling system failures and blown head gaskets are the norm here in Uganda.
The best Hiaces (pronounced by most here as the Japanese "high-achee" rather than "high-ace") are the so-called "Super Custom" available in RHD markets from 2004 to 2008. These had the three liter turbodiesel shared with the Landcruiser Prado TX and had low-range transfer cases and a locking rear differential as an option. The 2006 through 2008 models inherited several Landcruiser features, including the hot/cool console box. The Super Custom is what our company uses to ferry people up country here in Uganda and also in Congo; they have the Landcruiser drivetrain, including far better cooling, though the 3.0TD is still under the passenger seat (and gets hot!).
If I had to choose a Hiace, it would be a 2007 Hiace Super Custom. Wonderful vehicle, particularly when fitted with the five-speed and the locking rear diff.
If we're talking utility vehicles as a base for an expedition vehicle, a 2004 or 2005 Hiace pickup (Heavy Ace .75 tonne) would be a good starting point, particularly with a tri-fold bed (the bed section can be easily modified or removed, but it gives a nice flat starting point).
