Probably cheaper to buy a second hand camper trailer than modifying a standard 6X4 trailer into an offroad camper trailer. There are some real bargains out there. By the time you purchase new axle, springs, hitch, tent and all of the modifications it would work out better and cheaper to buy one.
I tried it with my ox trail 6 turn axle to make it higher tent floor wouldn’t touch the ground and nearly ripped so put it back the right way tent on top of 6x4box trailerMaybe maybe not. Won't know till you weigh it sadly. They are cheap to replace so probably worth it. If you choose to keep the slipper springs they are a simple swap later. You can spring over the axle to give you more height which if it's got 300mm sides you will prob need to to get your tent side height correct.
Unless you use an oztrail camper six tent which suits 300mm sides
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