मैं अकेला ही चला था जानिब-ए-मंज़िल मगर लोग साथ आते गए और कारवाँ बनता गया - Purnesh Upadhyay

chug chug is generally heard from diesel engines(Mostly those from American Loco Company or the alcos)-its the sound of engine when it notches up or down-you generally get a screeh or frictioning sound when the breaks are applied from under the wheels

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