Mercury 1999 Mountaineer Owner's Manual page 190

Roadside emergencies
If the vehicle is towed by other means or incorrectly, vehicle
damage may occur.
Do not tow with slingbelt equipment. Ford Motor Company has not
developed or approved a T-hook or slingbelt towing procedure.
A towing manual is available from Ford Motor Company for all authorized
tow truck operators. Have your tow truck driver refer to this manual for
proper hook-up and towing procedures for your vehicle.
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