Weird brake wear

[dna]

I have an 03 H2 with 123k miles, which I've owned since new. I just did the very first brake job on it. The fronts had 5% left (just before the warning tab) but the backs had 60% left.
Is this normal? Not only getting so many miles on the first set of pads but the very uneven wear between the front and back pads?

[GLBLWARMR]

This is normal across all vehicles. Most cars and trucks, my F350 included, have larger front calipers 4-6 piston where the rear are single and maybe double piston on stock setups. Most of your stopping power is applied via the front brakes, thus causing those pads to wear faster. I average 2 front pad changes to 1 rear pad change.