Proposed rule · 2026-12981

Federal Motor Vehicle Safety Standards; Modernization of FMVSS No. 135 To Accommodate ADS-Equipped Vehicles

NHTSA is proposing to amend Federal Motor Vehicle Safety Standard (FMVSS) No. 135, "Light vehicle brake systems." The proposed modifications would distinguish how regulations apply to vehicles with and without manually operated driving controls. The proposed modifications would clarify definitions, telltale requirements, performance requirements, and test procedures in the standard and remove sections that are no longer relevant. The stopping distance performance requirements, which address the primary safety purpose of the standard, would still apply to all subject vehicles. This rulemaking would remove unnecessary regulatory burdens and costs without detriment to vehicle safety.