Mud flap hight.

I "think" the relevant ADR stipulates a certain angle from the rear of the tyre contact patch, the mudflap must touch that line.
I'd aim for around 300mm and I don't think you would be far wrong.
Ideally the flap should stop mud, stones etc from contacting the rearmost point of the body/bumper.

I would go as low as possible but if to low when you have to reverse in mud or sand you may rip them off when they get caught under the wheels.

This is depending on how fare from the wheel and what angle.

Ours are about 110mm from the ground.

The ruling states that no part of the vehicle may be lower than the lower portion of the rim. There is a term commonly referred to as the 'scrub line'. Assume a diagonal line between front left & rear right, and the opposite, level with the bottom of the rims. No part of the car is allowed to hang below this plane.

Typically, about 100mm of ground clearance is accepted as the norm.

Sorry, i should of explained my question a little better.

I ment hanging mud flaps in front of the camper trailer below the mesh stone guard to help prevent stones damaging under the trailer.

If it is too low when you hit a dip in the road at speed this can flick stones towards the trailer defeating the purpose of it in the first place.

The best way i found was to load the vehicle and trailer and connect, then leave a gap that would not allow the flap to drag when on a track with the centre fairly high. I found if to low the stones would get flicked up faily high. I think my gap is about 80- 100mm when fully loaded, your fuel load also comes into it. Col

HI Kev, I also found by having the flap to long its easier to cut of once i started travelling. Your also not far from me im at Tolga. Cheers Col