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In this study several non-destructive test methods have been applied to as-manufactured automotive brake pads. The primary emphasis of our study is the formulation and development of ultrasonic methods where four independent velocity modes are measured on each pad. For two of the measurements, the ultrasound is propagated in-the-plane of the pad, while in two other measurements the ultrasound is propagated through-the-thickness (out-of-plane). Over 300 pads from five different manufacturers have been tested. In many cases, the ultrasonic data is compared with other testing methods including conventional compressibility tests, modal analysis, and hardness testing. In some cases, measurements have been made of several different batches of materials to test long term consistency of the material properties in the production environment. In other studies the production process has been deliberately altered to help establish specific cause and effect relationships.