4-6-6-4 "Challenger" Steam Locomotives in the USA

Great Northern

The Great Northern Railway bought two 4-6-6-4s from its subsidiary, the Spokane, Portland & Seattle Railroad These two ALCO-built, former SP&S road numbers 903 and 904, were designated Class Z-6 and were given road numbers 4000 and 4001 on the Great Northern. They had four 23 x 32 cylinders, 69" drivers, a boiler pressure of 250 psi, a tractive effort of 104,500 lbs and weighed 621,000 pounds.

The two Great Northern "Challengers" were sold back to the SP&S, number 4000 in 1946 and 4001 in 1950.

Class	Qty.	Road Number	Year Built	Builder	Notes
Z-6	2	4000-4001	1937	ALCO	These locomotives were bought from the SP&S. Ex SP&S numbers 903 & 904. Number 4000 sold back to the SP&S in 1946 and number 4001 sold back to the SP&S in 1950.

Class

Qty.

Road Number

Year Built

Builder

Notes

Z-6

4000-4001

1937

ALCO

These locomotives were bought from the SP&S. Ex SP&S numbers 903 & 904. Number 4000 sold back to the SP&S in 1946 and number 4001 sold back to the SP&S in 1950.

Specifications for Class Z-6
Wheel Arrangement:	4-6-6-4
Length:	119' - 8"
Drivers:	69" dia.
Weight on Drivers:	436,000 lbs
Locomotive Weight:	621,000 lbs
Locomotive & Tender Weight:	1,014,700 lbs
Grate Area:	152.3 sq ft
Cylinders (dia. x stroke):	(4) 23" x 32"
Boiler Pressure:	250 psi
Tractive Effort:	104,500 lbs
Tender Capacity:
Water:	20,000 gals.
Fuel Oil:	6,000 gals.

Specifications for Class Z-6

Wheel Arrangement:

4-6-6-4

Length:

119' - 8"

Drivers:

69" dia.

Weight on Drivers:

436,000 lbs

Locomotive Weight:

621,000 lbs

Locomotive & Tender Weight:

1,014,700 lbs

Grate Area:

152.3 sq ft

Cylinders (dia. x stroke):

(4) 23" x 32"

Boiler Pressure:

250 psi

Tractive Effort:

104,500 lbs

Tender Capacity:

Water:

20,000 gals.

Fuel Oil:

6,000 gals.

4-6-6-4 "Challenger" Steam Locomotives in the USA

Great Northern

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