May be a difficult one to answer but here goes, My 2012 350 diesel just turned 80,000 km. Out of this I think about 40k was towing a 8k fiver for three years and this year a 15 k toyhauler. Thinking ...
^This. If you even need front pads at 80k km, you've been ridin the brakes! Since you don't know how to tell if they're wore out by looking at them then I'd suggest doing nothing until you figure that out. You don't need rotors unless the old ones are warped, with that low of km. Drilled/slotted rotors are for race cars not big trucks. Don't waste your $ there.