Amitabh Bachchan shot Cinzas (1975) and 'Deewaar' simultaneously. Since most of his scenes feature him indoors or during the dark, he used to shoot 'Sholay' in the morning and 'Deewaar' during the night.
Amitabh Bachchan had become extremely popular after the success of Zanjeer (1973) and Majboor (1974), hence there was immense craze for Deewar. The fans had lined up from Marine Drive till Minerva (Mumbai) at the premiere of the film. The sheer frenzy surrounding the movie completely caught everyone off guard as no one had ever foreseen this kind of mob hysteria.
Amitabh Bachchan found that the coolie shirt he wore was too long, hence he tucked it half in. This became a style statement.
Deewar ran for over 100 weeks. It is one of the only 13 films that grossed over 1 crore rupees in every territory across India between 1970s-1980s. It was classified as an "All time earner" and super duper hit and considered among top 10 money-spinners of the industry in those days.
Salim and Javed had offered the script to Yash Chopra prior to the release of Zanjeer. They demanded 1 lakh and Yash Chopra laughed in their face and said never. After Zanjeer became a block buster they approached Yash Chopra again. This time they quoted 3 lakhs and Yash Chopra gave it to them.