Possible Clues:

• Grouser's forte
• Raising trivial objections
• Fault-finding
• Persistently finding small faults
• Grumbling, being bothered about parking
• Compassionate nurses quietly critical
• Censorious kind should keep quiet
• Complaining about right hog eating end of mutton
• Complaining of high pitched noise under vehicle
• Complaining vehicle has a metallic sound