Recently purchased a 2001 Ram 2500 Diesel. Have noticed that the cruise won't stay on, the wiper blades get stuck and brake lights don't work. Could they be related? Is this something I could fix?

 

yup. . .sounds like an electrical gremlin. . .

I'm willing to say you either 1, have a bad main ground(not uncommon on these trucks) and/or 2. the wireing harness to the transmission has been rubbed by a hanger enough to ground out (another common thing on that year model)