Well if I was guessing that truck likely has a timing chain so you should not need to change it. But with a truck with that many miles(regardless of age) you might or might not have things like Alternators,water pumps,fuel pumps,ect go out. You just never know, also aswell as transmissions. Things go out with no warning or they can last another 100,000 before they do. But other than those things just normal oil changes and checking fluids regularly.
I just bought a 96 Geo Prizm a couple month ago. I've done had to change the Oxygen Sensor,Timing Belt,fix turn signals(I was dumb and didn't check these when bought) and thats about it. This car has a timing belt which is required maintenance every 60,000 some miles. It had 135,000 on it when I got it so I just assumed it had factory belt on it and I was right. The mechanic told me it had the factory belt on it. Had I not changed it, it could have broke at any time which would have likely killed my engine and I would have been out the money I gave for the car. I am also planning on doing a fuel filter change as a spark plug change aswell since those are likely factory.
But anytime you buy used your gambling no matter what. It might sound,drive and shift good but that don't mean it will a month or two after you buy it. Things wear out.