GMC 2004 Sierra 1500 Pickup Owner's Manual page 457

V8 Engine
V8 Engine, Diesel
Similar
11. Connect the other end of the negative ( ) cable to
12. Now start the vehicle with the good battery and run
13. Try to start the vehicle that had the dead battery. If
8.1L Engine
the remote negative ( ) terminal, marked GND, on
the vehicle with the dead battery.
the engine for a while.
it won't start after a few tries, it probably needs
service.
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