{"data":{"id":"us/40-cfr-1037.231","jurisdiction":"us","citation":"40 CFR 1037.231","heading":"Powertrain families.","body":"See 40 CFR 1036.231 for provisions describing how to divide your product line into powertrain families.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER U—AIR POLLUTION CONTROLS","PART 1037—CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES","Subpart C—Certifying Vehicle Families"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"b00324b2a89c0a744b838696f446ae77e828b3ad3db478e7262f3bd6d6d3627e","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-1037.230","next":"us/40-cfr-1037.232"},"notice":"GroundRules: Original legal text. Not legal advice."}