I’ve had a water leak now for the past couple months, whenever it rains my passenger floor board becomes wet, seems like it’s coming from firewall but I’ve removed cowl and I can’t find anything that looks off about it. Let me add I have replaced the whole third brake light housing sealed up very good with black rtv, and the windshield is as far as I know oem. I’m not running my AC so I believe it has nothing to do with the HVAC system. I have tried to track it the best I can with a hose but it’s very difficult to pinpoint. Any tips on finding a water leak? Or anyone going through the same thing right now? By the way it’s a 2011 2.9 Colorado Ext Cab. Thanks everyone!!