DT 240 hub lateral play

Lolol

Yes take it apart clean it, replace bearings if necessary, in fact you might as well do that anyway whilst it’s apart.

Here’s the manual to help you. The tools it mentions are very expensive but you can buy a ratchet tool on eBay for much less. The other tools you might already have if you have bearing presses https://dycteyr72g97f.cloudfront.net/up ... EN_001.pdf