Old? I been towing with a 1965 Chevy Van (flat windshield type). Put a 292 6 in it many years ago, 90,000 miles later still pulling. Never had a problem with it or breakdown. Constant maintenance is essential and the reason it's lasted so long. Oil changes, trans. fluid & filter changes, keep greased (has king pins), etc.
Recently went a lot newer, bought a 1994 GMC Suburban with the towing package on it with all the coolers. Truck was in great shape, one owner, garaged, have all service records. So, again I keep it well maintained and so far no problems.