Auto stocks traded higher on Tuesday, April 15 after US President Donald Trump signalled that he might exempt tariffs on auto imports. The Nifty Auto index, which tracks 15 automobile sector stocks, rose as much as 3.54 per cent today, led by gains in major auto and auto component manufacturers like Samvardhana Motherson International, Bharat Forge, Balkrishna Industries, Tata Motors and MRF.