Hey there Austin! I have a 2004 Ford F150 pickup, and I think it is time to replace the brakes and rotors, but how will I know for sure it is time? I have 78,000 miles on it now and have not replace either brakes of rotors before.
There is really not a set time to replace brakes and rotors, because there are so many variables to consider. How you drive, weight of your vehicle, do you tow anything, are you a two footed driver, city of freeway driving etc.
I would remove all 4 wheels and do a brake inspection. I would bet your front brakes are getting thin and is about due for a change. As for the brake rotors, you can either have them “trued” (machined to make smooth again) or you can just replace them with new rotors.
The price of many small car brake rotors are really cheap these days, so replacing them might be a better longer term option than truing them. Why? Because when you machine a rotor you remove a thin later of the metal, which will cause the rotor to “warp” (not smooth) easier because the metal rotor will heat up faster with less metal than before. So, you might experience a brake shimmy when you apply the brakes, because of the warped rotors.
On your truck, which has a much heavier duty brake rotor than say a Honda Accord, you can usually true them once with out having a warping issue. So if I was you, I would replace the front brake pads and true the front rotors.
The rear brakes tend to last twice as long as the front, because the front do most of the braking so I would assume your rear brakes will be in good shape still at this mileage and nothing will need to be done now.
Hope that helps