Noticed a substantial leak after a first rain under the glove compartment. The mechanic said must be a loose draining hose ...how can I get to it and fix it

 

do some searching,sun roof, water leak, etc.
been here a million times.

 

If you google how to fix an H3 leaking sunroof you'd have a fine start.

Look at this thread....
https://www.hummerforums.com/forum/h...n-tubes-28548/

 

Remove the A pillar covers, sun shades, & oh crap handle above the passenger seat & the top covering should come loose. I might have missed a few things, but you'll notice what they are immediately.

If you pull the ceiling cover down a hair, you can peep in & see if the tubes are connected or not. Just open the moonroof & pour some water. You can then see where it's leaking from if that's not the case.

It seems intimidating (I know it was for me), but it's really easy once you get into it.