The below link* goes to the grease page of a winch manufacturer. Reading the description, wrong grease might be fatal. Wow. That's an extreme warning!
http://andersenwinches.com/aw/suppor..._menu_id=20479
Not doing any winch maintenance might be a better option in comparison? (This comment made in obvious jest of course. Yes even I every so often dismantle, clean, and lubricate my winches.)
The tube pictured on the webpage self-describes the grease type as Multi-purpose Silicon Teflon grease.
*Longer term participants in this forum will remember that I tend to post the this url link whenever the topic of winch lubricants comes up.