1994 GMC Safari Owner's Manual - Page 230

You should also use the proper viscosity oil your vehicle, as shown in for the following chart: RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST SAE VISCOSITY GRADE 011 FOR THE EXPECTED TEMPERATURE RANGE. HOT WEATHER F f LOOK FOR ONE OF THESE LABELS C + 38 100 + 80 + 60 + 27 + 16 +4 + 40 + 20 0 -7 - 18 SAE 1OW-30 IF NEITHER SAE 5W-30 NOR SAE 1OW-30 GRADE OILS ARE AVAILABLE, SAE 30 GRADE MAY BE USED AT TEMPERATURES ABOVE 40 DEGREES F (4 DEGREES C). SAE SW-30 PREFERRED / COLD WEATHER DO NOT USE SAE 1OW-40, SAE 2OW-50 OR ANY OTHER GRADE O NOT RECOMMENDED I L As shown in the chart, SAE 5W-30 is best for your vehicle. However, you can use SAE 1OW-30 if it's going to be 0°F (-I 8°C) or above. These numbers on an oil container showits viscosity, or thickness. Do not use other viscosity oils, such as SAE 1 O W 4 0 or SAE 2QW-SO. 6-12