GM Storm/Spectrum 1985-1993 Repair Guide

Fuel and Engine Oil Recommendations


See Figure 1

All Spectrum and Storms are equipped with a catalytic converter, necessitating the use of unleaded gasoline. The use of leaded gasoline will damage the catalytic converter. Both the SOHC and DOHC engines are designed to use unleaded gasoline with a minimum octane rating of 87, which usually means regular unleaded.

Oil must be selected with regard to the anticipated temperatures during the period before the next oil change. Using the chart, select the oil viscosity for the lowest expected temperature and you will be assured of easy cold starting and sufficient engine protection. The oil you pour into your engine should have the designation SG marked on the container. For maximum fuel economy benefits, use an oil with the Roman Numeral II next to the words Energy Conserving in the API Service Symbol.

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Fig. Fig. 1: Select an engine oil of the proper viscosity for the ambient temperature - 5W-30 is preferred for SOHC engines and 10W-30 is preferred for DOHC engines