I just installed a spare-tire mount and Browning BR-180 dual band antenna on my Jeep JK. Initial SWR testing show nothing higher than 1.4:1 across both bands so I didn't try to tweak it.
Then I put the spare tire back on and the SWR shot way up, over 5:1 and worse in some cases. Removing the spare again confirmed the problem, as the SWR dropped back down.
What can I do to resolve this? I know others with similar installations that work fine. I'm not sure exactly what's happening.
These pics are of my installation.