Analysis of literature bearing-fatigue life results shows that fatigue life is not a simple function of the widely accepted specific film thickness, λ, which is the ratio of the EHL film thickness h to composite surface roughness [sgrave]. Instead, the influence of film thickness on bearing life increases with increasing surface roughness; at about 0.20 micrometer (8 microinch) composite roughness life increases with the square root of h while at about 0.46 micrometer (18 microinches) life increases with h squared.