Because of aging fleets, high operational tempos (OPTEMPO), and harsh operating conditions in Southwest Asia (SWA), equipment renewal is currently an Army imperative. Recent Army expenditures for reset (return to combat-ready condition), overhaul, and recapitalization have been on the order of $10 billion per year. Although anecdotal reports suggest that the reset program has been valuable, there is still a need for quantitative analyses to measure its effects and inform decisions about when and how often a vehicle should be renewed. This study assesses the effects of vehicle age, OPTEMPO, SWA deployment, and reset on mission-critical failures and maintenance costs. Findings suggest that renewal reduces a vehicle0́9s mission-critical failures and maintenance costs by up to 50 percent per year, with the result that reset of heavy combat vehicles becomes cost-effective after four years. Additionally, OPTEMPO and location (not necessarily deployment) may be more important criteria than age when selecting vehicles for reset. The results of this study have implications for reset planning and funding decisions.