When is the last time you had a new serpentine belt installed? I always carry a spare on long trips. On your particular car, you only have one drive belt driving the water pump and if it breaks for some reason, you will overheat quickly. A spare belt cost about 25-30 bucks. That is pretty cheap insurance for long road trips.
As for the rest of it, just verify all fluid levels are correct and that the engine is in good tune. A well maintained Buick with only 117K, should be road worthy!
Good luck!