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Experimental data from the literature for a wide group of metallic materials including steel, titanium, copper, and aluminum alloys obtained under a wide range of fatigue testing conditions were examined for common trends associated with Stage II fatigue crack growth rates. Among these trends, the correlation between the striation data and Young’s modulus (E). Also, the linear relation between Paris parameters (m vs. log C) and its correlation with Young’s modulus. These trends are discussed in reference to fatigue crack growth rates under closure-free conditions. The results emphasize the importance of E on fatigue crack growth behavior of metallic materials and provide a basis to predict fatigue life of engineering components under various conditions. Comparisons are made with crack growth equations that are commonly employed in damage tolerance analyses.