So I finished swapping the interior all to LED. All of them are perfect except the drivers rear door, it is much dimmer than the rest. I swapped out 4 other LED's and one from a door that was bright and same issue...

 

check the plug.

could be a bad wiring job on the LED board.

 

Plug seems to be fine, with the old(normal) bulbs in there is no difference side to side. LED board? These are not boards just bulbs with multiple led's on them.

 

Something is lowering the voltage to that socket. My vote is poor connection somewhere as well.