My truck is also an 03 and is marginal on cooling @95F ambient anymore. It never used to be that way. I am wondering if 3yrs worth of oxidation is starting to take its toll on the aluminum radiator fins. It may not transfer heat as well as it used to.
I had it get hot off-road @100F recently, never had any problem in the past. Might be time for a bright shinny new radiator.