The reference for locomotives and railcars
Pennsylvania class J1
United States | 1942 | 125 produced
Builder's photo of No. 6456
Builder's photo of No. 6456

To meet the increased demand for heavy freight locomotives during the Second World War, the PRR turned to the C&O and used their T-1 as the basis for their J1. Because of this origin, they were given the nickname “War Babies” and were ultimately the largest 2-10-4 “Texas” class in terms of numbers with 125. They were built at the PRR's Juniata Works in Altoona.

With the booster on the trailing axle they achieved a starting tractive effort of 110,100 pounds (490 kN), while the boiler output of 5,644 hp was sufficient for higher speeds with heavy freight trains. Some of the locomotives had a frame cast in one piece. Depending on the source, these were the 60 members of subclass J1a.

A teething problem of the J1 was its rough running, which apparently arose from a mistake when taking over the blueprints from the C&O. This was soon fixed and at the same time the drivers were enlarged from 69 to 70 inches. With the switch to diesel, they became dispensable in their original role in the late 1940s. However, the PRR also found enough other tasks for them so that they were only retired between 1957 and 1959.

Axle config2-10-4 (Texas) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length117 ft 8 in
Wheelbase49 ft 3 in
Fixed wheelbase24 ft 4 in
Total wheelbase104 ft 0 1/2 in
Service weight572,640 lbs
Adhesive weight377,800 lbs
Total weight984,140 lbs
Axle load76,800 lbs
Water capacity21,000 us gal
Fuel capacity60,000 lbs (coal)
Power sourcesteam
Indicated power5,644 hp (4,209 kW)
Optimal speed37 mph
Top speed50 mph
Starting effort96,867 lbf
Booster15,000 lbf
Power Plant
Driver diameter69 in
Boiler pressure275 psi
Expansion typesimple
Cylinderstwo, 29 x 34 in
Grate area121.7 sq ft
Firebox area525 sq ft
Tube heating area5,995 sq ft
Evaporative heating area6,520 sq ft
Superheater area2,931 sq ft
Total heating area9,451 sq ft
Calculated Values
steam locomotive
last changed: 12/2023

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