Indian locomotive class WDS-6  The class WDS-6 is a diesel-electric locomotive used by Indian Railways for shunting and doing departmental works. The model name stands for broad gauge (W), Diesel (D), Shunting (S) engine. The WDS-6 is used all over India. The class was created in 1975 to address the need for powerful shunting locomotive that will be able to haul 20-24 coach rakes. The previous WDS-4 class was underpowered for this kind of operation. The WDS-6 locos consist of the YDM-4 powerpack (6-cylinder 4-stroke inline Alco engine, turbo-supercharged) placed on WDM-2 frames. They were manufactured by DLW varanasi and later Parel Workshops started building them using the kits provided by DLW. The WDS-6 can easily be recognized by their shot nose and flat-ended cab at one end. They were sold and transferred to industrial concerns and public sectors in huge numbers, but have IR road numbers on them.