SECTION 1. PURPOSE

This notice provides interim guidance relating to the excise tax imposed by § 4051 of the Internal Revenue Code on the first retail sale of heavy trucks, trailers, and tractors. Specifically, this notice provides interim definitions of the terms “chassis” and “body” for purposes of § 4051(a)(1) and for purposes of applying the safe harbor provision in § 4052(f)(1). This notice also requests comments on the interim definitions.