You gotta make sure you clean the metal where the pad seats really well. If there's hardware, replace it also...and clean UNDER the hardware. When you put the pad in the bracket, it should slide pretty smooth. If you have to force it in, that's not good. Also, make sure your slides are sliding freely.
What it sounds like to me is something is making your outer pad not push against the rotor as hard as the inner. So it almost had to be that outer pad getting stuck somewhere -- like the sliders frozen or it's really dirty where it seats/slides.
Make sure to coat the pad ears in some synthetic brake grease too.
Other than that, you can get more life out of the fronts by making sure the rears are properly adjusted at all times.
02 Ext Cab | 4x4 | 3.0 | M50D-R1 | 3" PA BL | 33x12.50x15 Dynapro M/T's | 15x8 Soft 8's