Over the course of the past 19 years, the Sound Insertion Loss test method has become an accepted method for rank-ordering the acoustic performance of automotive Body-in-White cavity fillers by some OEMs in the United States. In some cases Insertion Loss data is required for a cavity filler material to be approved for use in a particular manufacturer's vehicles. In 2010, a formal SAE Insertion Loss test specification was created, SAE Technical Standard J2846.To gain an improved understanding of the variation inherent to the SAE J2846 Insertion Loss test method, a Gage Repeatability and Reproducibility (Gage R&R) analysis was performed. Gage R&R is a statistical tool used to measure the variation in a measurement system due to repeatability (error due to equipment variation) and reproducibility (error due to operator variation). The Gage R&R procedure followed for this paper can be found in the Measurement Systems Analysis Manual published by the Automotive Industry Action Group. This paper will present the findings of the Insertion Loss Gage R&R analysis.