What lift and tyres are you running? This will have a big impact on your fuel consumption.
Just as a comparison mine is a 95, when it still ran the old OBD1 engine (with really low compression) running 2" lift, 30" tyres (stock gearing), spare on the roof rack, rear fully loaded with twin metal drawers and twin fridges towing a 1t camper trailer from Brisbane to Cape York and back including the OTT I averaged 17l/100.
On a trip to Tassie with a roof pod, same lift, OBD2 engine (much higher compression), reageared to 3.73:1 running stock 225/75/15 tyres fully loaded I averaged 12.5l/100.
Empty I have gotten a best of 10.1l/100 again on stock tyres and 3.73 gears.
Since changing to full OBD2 I know it's better when loaded but not measured yet.
This set up was getting better economy then yours...
I suggest some maintenance is required for yours, O2 sensors, maybe cat etc....