When Rocky was new to Sodor, Gordon and Edward were skeptical about his abilities, noting that Harvey could travel under his own power. Later, Edward carelessly left the docks before his cargo was properly secured, causing pipes to spill onto the Main Line. Edward was adamant that Harvey clear up the line, but the little crane engine was too small to finish the job quickly and as a result, Gordon crashed into the pipes. Edward returned to Brendam to pick up Rocky, who cleared the line and put Gordon back on the rails.
Since this incident, Rocky has become an invaluable asset to the railway. He is frequently called upon to lift loads and help out after accidents. He is based at the Sodor Search and Rescue Centre, but is seen at the docks and other places like Sodor Slate Quarry helping out. He also tells the other members of the search and rescue team about the calls to action.
In the eighteenth season, Rocky and James attempted to help Duck get out of a flooded track, but due to James leaving before Rocky's crane arm could be secured down properly, Rocky inadverdently knocked over a signal.
Rocky likes to lift heavy objects such as engines, coaches, and trucks. He is a friendly crane and helps the engines when there is an accident.
- One of Rocky's television series models is currently on display in Canada at Nitrogen Studios.
- Rocky does not have windows on the front of his cab, making it difficult for the operator to see what is happening.
- In Season 11, it was stated that Rocky was too heavy for Thomas to move, but since the CGI switch, Thomas has been able to move him.
- Since the CGI switch-over, Rocky's face has slightly decreased in size.
- Rocky will meet Roary the Racing Car, Theodore Tugboat and their friends in
- Rocky is best friends with Lucky Clover.