I have owned this truck for five years, 50000 miles and tow a trailer loaded with 9000 lbs in stop and go traffic 40% of the time and the trailer does have brakes on both axles. I have been working on this brake problem ever since with a lot of help from this site. I don't know how true this is but someone told me the other day that 98. 5 was the worst year for brakes. Is this true cause it feels like it. What I have done so far over time is changed pads four times, rotors twice, adjust rears and lube calipers and pins ever 3000, changed rear cyl to chevy and finally replace calipers and front lines. All this and they still get hot like 390 hot checked with a IF thermometer. Now my rotors are starting to show small hair line cracks. Could there be a problem with the hydra boost or something? Thanks