In order to provide current and updated information, the case for burning used automotive lubricating oil versus re-refining it has been reevaluated based upon the 1980 American economy and energy conservation posture. In these comparisons, the environment is considered within four scenarios ranging from unrestricted burning of used oil without government constraints to complete prohibition of burning thereby funneling all used automotive lube oils to redefining. Two other areas have been reevaluated in the context of burning versus redefining of automotive lube oils in the U.S. These are the material and energy advantage to be realized in terms of resource observation through either burning or re-refining and an estimation of the economics and profit potential currently available in the disposition of used lube oil. This study was undertaken because previous data and information related to the energy savings by re-refining used oils are no longer timely. Earlier reports were based upon acid/clay or other obsolete technology, and the disproportionate changes in costs of energy as compared to the general inflation rate have made simple extrapolation of earlier economic comparisons subject to error. It was found that environmental concerns as presently regulated do not alone provide a persuasive case for re-refining over burning of used automotive lubricating oil. However, in view of the increased use of paraffinic crude oil for the manufacture of automotive lubricating oil, production costs will rise and product yields will be lower. In this context, this study shows that the energy required to produce a gallon of lube oil from paraffinic crude oil is greater than that to produce a gallon of lube oil from used lubricating oil. As a result, the re-refining of collectible used automotive lube oil could conserve 43 trillion Btu's per year, equivalent to 7 million barrels of imported crude oil worth over a quarter billion dollars. Additionally, this study indicates that new technology such as solvent/distillation re-refining would provide a 26 percent after-tax return on investment based upon 1980 markets and costs.