Both 打颤 and 打战 mean shiver but I saw that in 兩岸詞典 they say that 打战 in the Mainland is not used “陸：今不用”. So which is the correct word to write for Mainland Mandarin?
打颤 is ok. Other translations include 颤抖, 哆嗦. I've never seen 打战 used in the Mainland, but 打寒战 (also 打寒颤) is ok (literally it means to shiver because of feeling cold, but it can also be used for someone shivering when experiencing a fright).
If you say 打战 in the Mainland probably it's gonna be interpreted as "go to war".