Federal Motor Vehicle Safety Standards; Air Brake Systems; Long- Stroke Brake Chambers

摘要

In response to petitions for reconsideration, this document amends the reservoir requirements in Standard No. 121, Air Brake Systems, for trucks, buses, and trailers equipped with air brakes. The agency believes that the amendments will improve the braking efficiency of such vehicles and reduce the number of brakes found to be out of adjustment during inspections. It will do this by removing a design restriction that tends to discourage the use of long-stroke brake chambers, a technology with potentially significant safety benefits.