I hear a hissing sound coming from back left tire, no one seems to know what it is. It is not the tire, any ideas?

your one is full time 4x4 could be the shocks?

having full time 4x4 make a difference bout shocks... It could have something to do with your gas tank... the fill tubes go from that side down over the tire into the tank. Maybe your gas cap isn't sealing properly? I dunno if you have a zj, wj or wk but if you have a wj (99-04) there is a fuel filter behind the frame rail in that corner that could maybe make noise ?

when is the hissing happening

ha i ment 4x4 WONT make a difference.. lol

it could be many. i agree with the shocks. it could be the vent for your gas take but i doubt you can hear it. check for air in your brake lines.

Most likely a vaccum leak

I have the same issue I have a 2002 grand cherokee or wj and it sounds like a vacuum leak its tucked between the fuel tank and quarter panel behind the driver rear wheel I've tried to look up what it is but have had no luck any >deas??

I’m having the same issue of anyone has any ideas please feel free to help

did this ever get resolved??? asking for a friend.......