Tried a new LED bulb
wow, lots of replies to that question. Ok, so I purchased a set of LED bulbs on Amazon. Only $20 for a pair of 921 bulbs used for backup. I installed the JDM Astar 800 lumens, but there are a lot of choices for a similar price. Be careful to check your rig, some of them with the projector lamps use a different backup bulb with a different socket. The results: Of course they are whiter at 6000k compared to the plain Jane yellow incandescent bulb. They are also much brighter. It's hard to judge based on the different color, but I'd guess about twice as bright. I changed one side first and that entire side was much brighter and easier to see in the backup camera. For the price I would recommend the change. If anyone used or tries a different bulb for a similar price it would be nice to know as well. I know some of the interior bulbs are also 921.