The Pacifics of the Central Railroad of New Jersey were loosely based on the Reading class G1, so they had a Wootten firebox. The first classes consisted of six G-1s built in 1918 and five G-2s from 1923. Like the later classes, they had been built by Baldwin.

When the CNJ got access to more soft coal, five G-3s were built in 1927. These had a narrower firebox with a width of eight instead of nine feet. Other improvements included a stoker, a mechanic lubricator, a feedwater heater and a larger tender. Five G-4s followed in 1930 which had smaller drivers and a smaller loading gauge for working through the tunnels in eastern Pennsylvania.

In 1945, the CNJ adopted a new class scheme. They now got the prefix P for “Pacific” and a number that denoted the tractive effort in thousands of pounds. So the G-1s and G-2s became the P-43, the G-3s became the P-47 and the G-4s became the P-52. The last ones were retired in 1955.