The Pajero's indy suspension design is far more senstitive to load than a live axle design and it tends to chop its rear tyres' inner edges when towing. The Owners Manual sets out special requirements, decreased payload etc etc when towing.
Mitsubishi also suggests towing in 4WD to spread efforts into both axles/diffs. Good sensible stuff from Mitsubishi, but plenty of ATGANI nomads don't see past "3500kg" and learn things the hard way when they need rear tyres at 8000km.
This is not a fault, nor a criticism of the Pajero, simply a characteristic of the suspension that was laid-out with a higher priority on handling (which it does better than most) than load lugging or towing. Keep this in mind, and towbar downs sensible so ride height/attitude remains close to where the engineers want it to be, and it's a capable tow car ... but out-tugged by Prado and Territory.
HTH