Western Pacific Challengers

The Western Pacific Railroad purchased seven 4-6-6-4s from the American Locomotive Company in 1938. These "Challengers" were designated Class M-100 and were assigned road numbers 401 through 407. They had four 22" x 32" cylinders, 70" drivers, a 265 psi boiler pressure, exerted 99,600 lbs of tractive effort and weighed 590,000 pounds.

The Western Pacific used its "Challengers" for freight service across the desert between Elko, NV and Salt Lake City, UT until they were retired in 1952.

There are no surviving Western Pacific "Challengers".

Specifications for Class M-100
Wheel Arrangement:	4-6-6-4
Length:	120' - 0"
Drivers:	70" dia.
Weight on Drivers:	399,000 lbs
Locomotive Weight:	590,000 lbs
Locomotive & Tender Weight:	991,500 lbs
Grate Area:	108.2 sq ft
Cylinders (dia. x stroke):	(4) 22" x 32"
Boiler Pressure:	265 psi
Tractive Effort:	99,600 lbs
Tender Capacity:
Water:	22,000 gals.
Coal:	25 tons

Western Pacific Challengers

References