GMC 1995 Safari Owner's Manual page 208

Your vehicle has a facial air bag system. Before attempting to do your own
service work, see "Servicing Your Facial Air Bag-Equipped Vehicle" in the
Index.
You should keep a record with all parts receipts and list the mileage and the
date of any service work you perform. See "Maintenance Record" in the
Index.
NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
Fuel
The 8th digit of your vehicle identification number (VIN)
shows
the code
letter for your engine. You will find the VIN at the top left of your
instrument panel. (See "Vehicle Identification Number" in the Index.)
Following is fuel information for the 4.3L (Code W) engine.
Use regular unleaded gasoline rated at 87 octane or higher. Use premium
unleaded gasoline rated at 91 octane or higher for high power performance,
when towing a trailer or with a high payload requirement. But when
operating with a light load as a normal condition, you may use middle grade
or regular unleaded.gasolines.
The gasoline you use should meet specifications ASTM D48 14 in the
United States and CGSB 3.5-92 in Canada. These fuels should have the
proper additives, so you should not have to add anything to the fuel.
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