EMPLOYEE WAS ASSISTING A COWORKER REMOVE A WIRE ROPE SLING ATTACHED TO A GREASE SERVICE TRUCK THAT HAD BEEN USED TO PULL THE TRUCK FROM MUD. WHILE BENDING AND REACHING, THE EMPLOYEE EXPERIENCE D A LOWER BACK STRAIN. THE SLING WAS 1 1/2"" IN DIAMETER WEIGHING APPROX 100 LBS.