Northern Pacific Railway No. 3617

Northern Pacific Railway No. 3617 is a restored SD45 diesel locomotive originally owned by the Northern Pacific. It was built in 1967 as a replacement to older locomotives that were "trade-ins" for new units in the 1960s. NP 3617 now is a display piece and is in restoration for operation at the Lake Superior Railroad Museum.

History
In the mid-1960s Northern Pacific started to replace its first-generation diesel locomotives. Northern Pacific's first second-generation diesel locomotive purchases came from General Electric. But Northern Pacific wanted higher horsepower, and thus turning to General Motors. The result was the SD45. The SD45s were all painted in NP's black and gold freight scheme.

NP 3617 was a part of 30 SD45s purchased by Northern Pacific from 1966-1968. NP 3617 was built in April 1967. At 3,600 horsepower, the SD45s were the largest on Northern Pacific's diesel locomotive fleet. NP 3617 operated on the Northern Pacific only 3 years until the 1970 merger into Burlington Northern. The 3617 received a new number, 6417 and was eventually repainted in BN's cascade green scheme. The 6417 then operated on the Burlington Northern until its retirement in March 1987.

Wisconsin Central Ltd. began operation in October 1987, and the 6417 was brought out of retirement and back into service on the WC. The locomotive would be renumbered twice more, to 6485 and later 7495. Canadian National acquired the Wisconsin Central in 2001. The 7495 continued as a WC unit until 2007, when it was donated to the Lake Superior Railroad museum in Duluth, MN.

From 2007 until 2015, extensive restoration was completed to restore the locomotive to its original Northern Pacific appearance. It was at one point sent to North Dakota to be repainted. Among being repainted its gyrating-warning light on its nose was restored. Its restoration, as of October 2015, was largely completed, but some electronic equipment is to be installed to complete its restoration as an operation unit.