GMC 2001 Sierra 1500 Pickup Owner's Manual page 342

CAUTION:
The recovery hooks, when used, are under a lot
of force. Always pull the vehicle straight out.
Never pull on the hooks at a sideways angle.
The hooks could break off and you or others could
be injured from the chain or cable snapping back.
NOTICE:
Never use the recovery hooks to tow the vehicle.
Your vehicle could be damaged and it would not
be covered by warranty.
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