The results of this study, involving a limited sample of vehicles from medium to large fleets, indicate that inservice non-road-friendliness of air-suspended triaxle groups is a manageable issue once the OE-type approval test is in place. The effects of suspension, and particularly shock absorber wear in eroding the benefits of road-friendliness are incremental rather than dramatic. The emphasis in controlling road-friendliness in-service could therefore lie in the introduction of auditable suspension maintenance regimes utilising the following activities at prescribed intervals: shock absorber removal and inspection for defects, dynamometer testing and shock absorber replacement.