By Nancy Pope, Historian and Curator
For more than a decade many U.S. letter carriers made their daily rounds in vehicles that could be immobilized by three inches of snow, tip over if driving around a corner more than 25 mph, caught in a wind gust, or even by large dogs jumping on them.
By the 1950s The Post Office Department needed to get letter carriers off their feet and into vehicles in response to the growth of suburban areas across the country and the growing increase in mail volumes, including packages.
They began using three-wheeled lightweight quarter-ton trucks known as mailsters. Postal officials first tested mailsters in 1950 in Miami, Florida. Over the next few years officials looked at a variety of vehicles including the mailsters, which were cheap to manufacture. Mailsters got their first big test in 1957, delivering carriers to their destinations in a cluster of cities in Georgia and Florida at first, soon after appearing in Washington, D.C., Wichita, Kansas and Paterson, New Jersey.
By 1959, approximately 5,000 routes were covered by mailsters. By 1961 carriers were driving around in 8,400 mailsters, with more on order year after year. At least seven different companies produced mailsters. By the early 1960s, they comprised one-third of the Post Office Department’s vehicular fleet. Unfortunately, the mailsters did not work out as well as officials had hoped.
Along with the challenges of snow, tight corners, wind gusts and big dogs, the vehicles’ 7.5 horsepower engine left them creeping along in city traffic. They were prone to breakdowns with everything from brake and clutch failure to broken front axles and gear shift levers. The Department did not end its love affair with the mailster, but instead asked for several design changes to answer some of those problems. Steering wheels replaced handle bars, cargo capacity was increased, heaters and windshield defrosters were added, and sliding doors took the place of curtains.
But by the end of the 60s the Department recognized that no amount of alterations to the mailster could make it the vehicle they needed to cover the nation’s 42,000 motorized carrier routes, let alone the thousands of routes expected over the next few years. The mailster continued to be a hotbed of flaws, including defective front axles, defective and inferior shaft linkage, defective drive couplings, defective universal joints, defective door locks, defective fuel pumps, and defective brake pedal mountings. The Department began replacing the mailster with the larger, and far sturdier and reliable, Jeep.