What I would do is to change all the fluids and filters. You really have no way of knowing if this was done or not on a timely basis. Make sure you find all the grease zerks and give them some good shots of grease. I would consider changing out the antifreeze/water mixture as well because some of the anti corrosion factors may be worn out at this point.
Some money spent now may mean a lot more longevity.
Oil and grease are pretty inexpensive in the long run.
Make sure you check the front axle oil as well.
Enjoy!
John