From the July 15, 2015 Mid Week "Looking Back."
A comparison was made in regard to power, economy and durability among all makes of automobiles, regardless of the price. Thirty miles per gallon of gas and 3 to 70 mph on high speed.
Thrice winner of the Glidden Tour, "Metz" five passenger automobile $495. The "Metz" 2 passenger runs about $495.
Aaron Johnson got a Ford automobile a couple days ago and has been traveling his rural mail route east and south of Sycamore in half the time he had done on a horse.
Andrew Winans bought a handsome, swift-running Metz runabout for rural county #3 duty west and northwest of Sycamore.
Upkeep of one of these machines is less than for a pair of horses, service rendered prompter and expected to be used for ten months a year.
So, evidently, the new automobiles were considered to be of great service to the post office, but it sounds like the carriers had to buy them themselves.