98 s-10 blazer tranny leak under drivers side door

I drove home from work all was fine, when I went out to blazer later there was a huge tranny leak under drivers side door. Any ideas what needs replaced? I know very little about vehicles or if this is a big deal. Thanks for the help..........

I drove home from work all was fine, when I went out to blazer later there was a huge tranny leak under drivers side door. Any ideas what needs replaced? I know very little about vehicles or if this is a big deal. Thanks for the help..........

Welcome to AF.
First thing you need to craw under there and have a look at it.
Look for where the leak is comong frommand report back.

Do not drive it untill you fill it up with fluid and see where it is leaking and post back.