L-3
The next development of the Mohawk type was that of the dual service locomotive, capable of working passenger as well as freight trains. Passenger service required the ability to work at 80 mph, as opposed to the 60 mph required of freight. The NYC's fleet of Hudsons, 275 strong though it was, was proving inadequate to handle peak traffic demands, and some dual-purpose power would fix the problem nicely, as well as giving the ability to handle express freight and mail services.
Two L-2 locomotives were given modifications for dual service work; higher boiler pressure, smaller cylinders, light-weight reciprocating parts, dynamic counterbalancing of the drivers, roller bearings on all axles, etc. The success of these modifications prompted the construction of the L-3 class in 1940, 25 of which were built for dual service and the remaining 40 for freight only.
All L-3 locomotives were given axle spacing that could accommodate 72" drivers, but only one was ever fitted with such. This locomotive, #3000, paved the way for the final class of Mohawks on the Central, the L-4.
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