I'd hate to waste the money for cross drill rotors on a Jeep Liberty... The pads I put on were Wagner ThermoQuiet ceramic blend pads. I checked them today and there was hardly any inner pad (piston side) left......6000 miles..... Wife is not a brake rider either.

 

If one pad is wearing more then the other, I'd suspect the caliper is binding.
Did you apply fresh silicon grease to the caliper pins and are the seal boots in place.

Just a thought...

 

I went to firestone auto care center yesterday, they told me there's nothing wrong with my brake. The reason why I feel the vibration is beacause my tires were too big on the front. So when I turn my steering wheel all the way to the right my tire hits the side wall and thats why i feel the vibration, can this be possible? my tire size is 285/50R20.