Twenty vehicles were tested on a short-trip winter driving schedule in order to study the effects of some engine, oil, and fuel variables on engine rusting. The results show that: rusting in the V8 engines was worse than in the 6-cyl engines; the effect of exhaust gas recirculation is small but it does increase rusting; unleaded fuel reduces engine rusting; ashless oil formulations may not be satisfactory even with unleaded fuels; present laboratory engine tests may not be adequate to predict oil performance for six months of severe winter service.
