Although they were good haulers and well liked by engineers, poor design and constant mechanical problems plagued them for their entire lives and they were among the first of the Milwaukee Road's electric locomotives to be retired.

When the Milwaukee Road decided to electrify the Coast Division in 1917, it attempted to re-equip with equipment bought from General Electric.

The United States Railroad Administration, however, dictated that the order for electrical equipment be split between GE and Westinghouse.

At each end of the quill, seven-armed "spiders" stuck out between the spokes of the driving wheels, and were connected to the drivers by coil springs.

The Milwaukee Road's new EP-3s, unlike the trouble-free New Haven boxcabs of similar design, immediately started experiencing broken axles and frame members, cracked wheels and spokes, and deformed suspension springs.

There was too little lateral play in the drivers, causing excessive wheel wear, and the frames were breaking under the stress of high-speed operation through twisting mountain rights-of-way.

The Milwaukee Road's Electrification Department under Reinier Beeuwkes had come to differing conclusions about the best course of action to take, and resisted Baldwin's recommendation that all ten "Quills" be cut in two.

The entire series was effectively converted to single-end operation and were fitted with Commonwealth Delta idler trucks of better design than the originals to help guide the locomotives into curves.