An unremarked silver and black NJ Transit engine is the Eli Manning of locomotives. Unlike the recently retired Giants quarterback, NJ Transit has no immediate plans to let this athlete of the rails — the oldest engine on the tracks — quit.

NJ Transit engine 4100 is a microcosm of state commuting history. At age 50, 4100 began its career as one of 13 boxy GP-40P passenger engines, built by General Motors and purchased by the New Jersey Department of Transportation to keep commuter trains running on the bankrupt Central Railroad of New Jersey.

The 4100 is like the winner of “Survivor," outlasting that railroad and Conrail, which absorbed the CNJ and other bankrupt northeastern railroads. It was still working when Conrail quit the commuter train business in 1982 and continued running when NJ Transit rail operations was created to keep the commuters moving in.

“It is almost unimaginable these locomotives are still in service after more than 50 years of continuous service. About 20-25 years is the expected life expectancy of a locomotive,” said Frank Reilly, President of the Central Railroad of New Jersey Historical Society and a former railroad employee. “This goes to show that good maintenance and caring can keep equipment going for many years past their life expectancy.”

Locomotives are not like cars that may get bought and sold once or twice and are finally junked after 10 to 15 years of rolling up the miles.

“Unlike most road vehicles, railroad locomotives of all types can last a very long time, and usually do, even if they get bought and sold repeatedly,” said Russell Quimby, a retired National Transportation Safety Board crash investigator and safety consultant. “4100 is highly unusual, not only due to her longevity, but because ‘she’ has remained in the relatively same location and service as when she started.”

He compared the engine to a dedicated employee who is still working after 50 plus years in the same job.

“The 4100′s survival is also a tribute to the long line of maintenance men and women who have worked to keep her ‘alive’ all these years,” Quimby said.

Arrival of the 4100 and its dozen sister locomotives in New Jersey was a stopgap measure to keep commuter trains rolling on the bankrupt Central Railroad of New Jersey. State officials prevailed upon the Baltimore and Ohio railroad to purchase the new locomotives and lease them to the NJ DOT for exclusive use on CNJ passenger trains, Reilly said. They replaced engines built in the 1950s that had hit the end of their useful life at age 15.

“I was working on the CNJ in 1968 when the GP40P’s arrived and they were beautiful,” Reilly remembered. "That had great power and pulled a passenger train out of a station much faster than previously used locomotives.”

Three GP-40P commuter engines bought by NJ DOT are seen at Raritan Yard in 1974. After a rebuild in 1990, some of these engines are still hauling NJ transit trains today.

Under an agreement between the B&O and NJ DOT, the locomotives were painted in the B&O royal blue and yellow paint scheme. If the CNJ discontinued commuter service the GP-40P’s would go back to the B&O. The B&O retained ownership until they were ultimately sold to NJ Transit in 1983, Reilly said. NJ Transit paid tribute to them by repainting 4109 in CNJ colors as part of its 40th-anniversary heritage program last year.

“The maintenance crews liked them because they were easier to work on,” Reilly said. “Commuters loved them because reliability of their ride greatly improved.”

The 4100 was the first one, built in October 1968 and delivered wearing CNJ number 3681. NJ Transit later bought other GP-40′s from different railroads and had them rebuilt into passenger engines in the 1990s. Lionel trains even made a model of NJ Transit GP-40 4302, in case you want a commuter train under the Christmas tree.

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How did they last so long?

“The GP-40P locomotives had a long-standing reputation for power and reliability. By 1990 they had reached the projected end of their useful life after having been operated almost every day for 22 continuous years,” Reilly said. “The engines began experiencing electrical and mechanical problems that averaged four failures per week,” he said.

NJ Transit officials determined it was cheaper to overhaul the locomotives than buying new ones, said Reilly, who regularly attended the agency’s board meeting up to 2000. NJT staff determined the cost to rebuild each locomotive was approximately $900,000 compared to the cost of a new passenger locomotive of about $2.2 million, he said.

Rebuilding didn’t just make them more reliable, it made them faster.

"They were also equipped for 100 mph service so they could be used on some North Jersey Coast Line trains that traversed a small portion of the Northeast Corridor Line,” Reilly said. They are now mainly on the diesel lines of the Hoboken Division.

Their story isn’t over.

NJ Transit officials said the 4100 still has a future, even though the state allocated a $500 million bond last December which includes buying 17 new locomotives to eventually replace the oldest GP-40Ps. But new engines are years away from delivery.

“Number 4100 is in revenue service and there are no immediate plans to retire it,” said Lisa Torbic, a spokeswoman.

That doesn’t mean life is easy keeping a half-century on the rails in regular service. Think about having to find parts for a 50-year old car.

“Parts are available for the GP40s and on occasion, there can be some lead time to locate something particular,” Torbic said.

Larry Higgs may be reached at lhiggs@njadvancemedia.com. Follow him on Twitter @commutinglarry. Find NJ.com on Facebook.

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This article is part of “Unknown New Jersey,” an ongoing series that highlights interesting and little-known stories about our past, present, and future -- all the unusual things that make our great state what it is. Got a story to pitch? Email it to local@njadvancemedia.com.

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