1994 Chevrolet Blazer Owner's Manual - Page 247
1994 Chevrolet Blazer Manual
Page 247 highlights
You should also use the proper viscosity oil for your vehicle, as shown in the following chart: RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST SAL VISCOSITY GRADE 011 FOR THE EXPECTED TEMPERATURE RANGE. [ + 60 HOT WEATHER C LOOK FOR ONE OF THESE LABELS - +38 - +27 - +16 -+4 + 40 f 20 - -7 I COLD WEATHER - -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). DO NOT USE SAE 1OW-40, SAE 2OW-50 OR ANY OTHER GRADE OIL NOT RECOMMENDED SAE 5W-30 PREFERRED As shown in the chart, SAE 5W-30 is best for your vehicle. However, you can use SAE low-30 if it's going to be 0°F (-1 8°C) or above. These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils, such as SAE 1OW-40 or SAE 20W-50. If you cannot findoils with the new "starburst" symbol on the front of the container, you should look for and use oils containing the following three things: 6-11