TTCI is investigating the effects of tread braking on wheel wear and tread damage by monitoring the performance of eight cars with disabled brakes operating in otherwise normal revenue service conditions. FRA granted an enforcement discretion for these eight cars to operate in revenue service with disabled brakes for up to three years as part of this study. Comparisons of the wheel wear patterns, wear rates, and tread damage will be made between wheels with disabled brakes and wheels operating in the same trains and/or same cars with fully functioning air brakes. An inspection was conducted on the one wheelset removed from a truck with disabled brakes and shelling was clearly visible on the tread of both wheels. This indicates that braking is not absolutely necessary to generate shelling on wheels.
Wheel shelling found on one of the removed wheels that had never been exposed to tread braking. - Photo credit TTX