The foremost reason for not using wheel spacers is they are illegal in all states for highway use. Whilst they may be great to gain clearance for off road tyres, wheel spacers are simply prohibited from use on any gazetted Australian road or track.

Wheel spacers bolt to the axle, with tapered wheel nuts, in the same way that a wheel does. Then the wheel bolts to the spacer via wheel studs integral to the body of the spacer. In doing so, the inner wheel nuts become covered and unreachable. Visual inspection or regular maintenance to check the lugnut torque is impossible without first removing the road wheels.

Wheel spacers also greatly increase wheel track. For general use, this far exceeds any original axle and wheel bearing tolerances. Wheel alignment is also compromised resulting in diminished handling and braking characteristics which could have serious consequences.