Truck Towing Capacity

Carrying capacity is your pay load not your GVM (gross vehicle mass). GVM is the max weight of the truck and it's load.
The truck should have a GCM (gross combined mass) rating on the compliance plate. Basically this is your overall weight of the truck and trailer loaded.
You have to take into consideration your towball weight.
In most states I believe your loaded trailer cannot be heavier than the towing vehicle.
Their is always a lot of debate around this subject and this is my understanding of it. I'm happy to be corrected.

Joe.

Any of the light trucks I’ve used have had no more than 3500 kg tow rating.
If it has a 3500 kg payload you’ll either have to have a LR/MR license or derate to 4495 kg GVM which will leave about 1500 kg payload. I don’t rate light trucks for towing at all in comparison with modern 4wd’s at the weight you are talking unless you also need plenty of payload.

Check your the towing capacity of what ever you buy eg, my Isuzu nps 300 has a towing capacity of 3500kg but it not legal with a 50mm tow ball, has to be a pintail hook to get 3500kg. with a 50mm ball its only legal to 2850kg Not many truck owners are aware of this law the bigger the truck the lower the tow capacity with a 50mm ball
National heavy vehicle regulator (VSG-16)

You could try the Iveco Daily 50c. Good spec, 8speed auto, 3.5 tonne towing, and about 2 tonne load capacity.

Iveco Specs

Gordon - The Mazda/Ford T-series 3 tonne trucks were fitted with the 4 cyl 3.5L and the 6 cyl 4.1L engines.

The 4 cyl is useless for towing, and the 6 cyl is not much better. The 6cyl only makes 100HP (74.5Kw).

They are getting pretty old now, and most have corrosion in the cab. The "splitter" section in the transmission will give you trouble, if you start towing with them.

Far better to look for a 4-5 tonne Isuzu, an FSR400, FSR450 or even an FSR 500.
These trucks were powered by the 6 cyl, 6.5L, 6BG-1 engine, which produces 160HP and lots of torque.
They are also one of the toughest, longest-life, Jap truck diesels built. You can turbocharge them to 185HP.

I have an '89 FSR500 5 tonner, it can legally tow 6.5T and it tows a 4.5T trailer with ease.
Mine is fitted with the 6 speed transmission, it's a very pleasant and easy-handling truck to drive - and it will do (sshh! - 130kmh) - much more than the speed limit.

These engines will last for a million kms without overhaul, so don't be put off by high kms. Just look for corrosion in the cab, particularly in the floors (leaking windscreens cause this).

My truck had done 700,000kms when I bought it as salvage (it had been lightly damaged in the front).
I repaired the panel damage (easily done, and parts are plentiful and reasonably priced), fixed anything else that needed fixing, and it cost me under $6000, all up.

If you can't find one of these in reasonable shape, look for the later FSR's with the 7.1L 6HE engine (these have vertical exhausts fitted, an emission laws requirement that the earlier trucks didn't have to comply with).
These trucks are just as good, and there's probably more of them to choose from.

Cheers, Ron.