22626 SBC-MAS Double Decker - எப்பவுமே டாப் டக்கர் - Vijay Baradwaj

Strongest in terms of tractive effort is WDG5. In terms of raw HP, it's WAG9H.

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Thanks for rectification

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WDS hauls only empty passenger or freight rakes, not used for mainline operations :P

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Thanks for refining my answer in technical terms. ;)
By the way, what's the difference between WAG 9 and its newer version 9H ?

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9H is the heavier variant. A normal WAG9 weighs around 123 tonnes but a 9H weighs around 132 tonnes. Apart from that, there's a different application software in WAG9H. Apart from these two differences, they're pretty much the same.
WAG9H has a higher tractive effort compared to WAG9.
Newer WAG9 locos turned out by CLW are all WAG9H locos :)

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