2 Chainz -- Posts SIZZURP Video Online 1 Day Before Arrest

2 Chainz posted a damning video of what appears to be the rapper and his crew in the middle of a serious SIZZURP session ... just 1 day before he was arrested for drugs, TMZ has learned.

The video was made specifically for Vine -- a video website that features clips that MUST be 6 seconds or less (it's sorta like Twitter).

In the footage posted by 2 Chainz on June 10, you can clearly see the rapper next to a table filled with what appears to be the ingredients for Sizzurp (cough syrup bottle, sprite and cups).

2 Chainz posted a similar Vine video the day before (June 9) ... but in this clip, you can clearly see 2 Chainz puffing away on what appears to be a fatty joint.

While the videos feature members of 2 Chainz's crew drinking from the double-cups on the table, you never see 2 Chainz taking a sip.

We broke the story ... 2 Chainz was arrested at LAX on June 11 for possession of narcotics after TSA agents claim they discovered Promethazine and pot in his luggage.