I actually just fixed mine. Thought the cables were bad, but as it turned out it was just the ends on the positive cable. The worst was the flag treminal on the main battery.
I just bought the best 3 guage lugs and wing post marine terminals that carquest had and just crimped and soldered lugs on all my ends- positive and negative and put a good 4" lenght of heat shrink over all my work areas and called it done.
My truck has never started this good since i've owned it............