<p>Creep-fatigue is a lifetime-limiting damage phenomenon common to all high-temperature components that experience steep thermal gradients and has been relatively well studied in traditional high-temperature materials. However, increasing automotive engine temperatures and the financial incentive to utilize secondary alloys has driven a strong demand for understanding creep-fatigue effects in a new generation of aluminum engine alloys. This work investigates the creep-fatigue crack growth rates and associated damage mechanisms of 319 aluminum alloys with variation of microstructural attributes and chemical composition. Mechanical testing was conducted with and without application of a two-minute compressive dwell during fatigue cycling, and at room temperature and 250&#xa0;°C. The dwell/250&#xa0;°C condition representing engine service conditions exhibits unique damage mechanisms associated with dislocation creep that provide insight into operable strengthening mechanisms. Recommendations are made for material processing to improve performance of recycled alloys in creep-fatigue loading to promote their utilization in situations requiring high-temperature structural integrity.</p> Graphical Abstract <p></p>