STEERING, AXLE & RUNNING GEAR CHANGES
The information from the DFT states: “Alteration of the type and or method of suspension or steering constitutes a substantial change.” While this appears to be bad news for gaining MOT exemption, we have also found that “in respect of axles and running gear changes made to improve efficiency, safety or environmental performance”, they are acceptable. So if the brakes have been uprated on a car that’s old enough for MOT exemption, this seems to be OK – as does adding a servo, for example. The same applies to suspension upgrades, although could lowering a vehicle really be regarded as an improvement in efficiency, safety or environmental performance? Changing the diff ratio in the back axle of a Capri for one that makes the car more economical and reduces engine revs at motorway speeds could be regarded as acceptable.