The factory front upper shock mounting arrangement is the weak link on these trucks. A cantilevered bolt using only the frame wall thickness. These brackets correct that by supporting the other end of the shock bolt.
Even if you aren't lowering your truck they are a great addition. The shock absorber technology of today loads shock mounts more than old technology shocks.
Thanks for the replies, started tearing into my front end tonight. Will be looking to add these, I am going to keep it stock but I noticed the top bolts were not super tight on the shocks to begin with. Seems like this would help support the load of the shock for sure.