By 1951, New York Central had its post-war fleet of trains going at full strength, and due to declining ridership it probably did not place many orders for new passenger cars other than the ultra-lightweights of 1956. Instead of new trains, the front-cover ad (again, the cover shown below is the back cover) focuses on destinations such as New England, Niagara Falls, and the Adirondacks.
Thanks to post-war updates, some of the coast-to-coast sleeping car services have improved time since the 1947 timetable. In 1951, the Lakeshore Limited sent a car to San Francisco every day, but it would go on the Overland Limited every other day and the California Zephyr every other day. The Pennsylvania sent a car on these trains on the days the New York Central did not, so coast-to-coast passengers had their choice of routes even if they couldn’t take each route every day.