Similar thing here, but you might be able to get wider offset wheels to increase the clearance. Its when the axle takes more weight on one tyre that you run into issues - the tyre on the high side with the weight on it gets ground onto the tub of the trailer and possibly goes POP... Converted a mates work trailer to having brakes - custom built caliper brakets etc and found out that the calipers and tyres had this issue (insufficient clearance to the sides of the trailer tub). Had to scallop into the tub to get the calipers into position, bloody mongrel of a design. Trailer was built to absolute maximum dimensions and minimum clearance to do it. Having brakes on it totally changed the behaviour of the trailer on the road though, stopped all surging and shoving and turned it into an absolute kitten to tow. Was a real bitch before the mod.
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