GMC 1995 Safari Owner's Manual page 173

Jump Starting
If your battery has run down, you may want to use another vehicle and some
jumper cables to start your vehicle. But please follow the steps below to do
it safely.
I
NOTICE:
Ignoring these steps could result in costly damage to your
vehicle that wouldn't be covered by your warranty.
Trying to start your vehicle by pushing or pulling it won't work,
and it could damage your vehicle.
To Jump Start Your Vehicle:
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
1
NOTICE:
If the other system isn't a 12-volt system with a negative
ground, both vehicles can be damaged.
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