Deconstruct a hero

Tow Mater- Cars 2
Mater was just an average tow truck living in a small town until a race car showed up one day and turned his life around. This race car, Lighting McQueen, became Mater's best friend. McQueen got asked to race in a world cup race and he invited Mater to go with him. Mater wasn't the best at acting mature in social situations, so he embarrassed McQueen and he told Mater to just go home. During his time in Japan (where the first race took place) Mater had a tracking device placed on him with a picture of the bad guy that secret agent spies were looking for. Mater was found by these spies and they had assumed that Mater was a secret agent spy as well.
During the big race that McQueen was in, all the racers were only allowed to use a special kind of fuel, Alinol, in their car. This was all fine and dandy until cars began to combust and people were blaming it on the oil. People were worried that someone could seriously get injured due to this unexplained explosions.
Mater figured out that the bad guy that they were looking for was the cause for the combustion of the fuel. He did everything he could to get to McQueen (who was still using Alinol) so that he wouldn't get killed by the combustion of the oil. Mater single handedly figured out that the creator of Alinol was also the destroyer of it.
I see Tow Mater as a hero because his adventure, even though he did it unknowingly, helped to save his best friend. He put his own life at risk in order to save his best friend. That to me, is the idea of an ideal hero. The kind of person who will do anything and everything to save the one they love.