The M1 was a class of steam locomotive of the Pennsylvania Railroad (PRR). It was a class of heavy mixed-traffic locomotives of the 4-8-2 "Mountain" arrangement, which uses four pairs of driving wheels with a four-wheel guiding truck in front for stability at speed and a two-wheel trailing truck to support the large firebox needed for sustained ...

Pennsylvania Railroad 6755 is a preserved M1b class 4-8-2 "Mountain" type steam locomotive built in June 1930 for the Pennsylvania Railroad by the railroad's own Altoona Works as a member of the M1b locomotive class for mainline freight service.

First built in 1923, The M1 and the later subclasses, the M1a and M1b saw service on the entire system. Orginally designed for dual Passenger and Fast Freight service, later years saw the entire fleet of 301 4-8-2's assigned to freight service only. Like most PRR Steam Locos, the M1 class saw upgrades to help performance.

The Pennsylvania Railroad's Juniata Shops in Altoona, PA, outshopped a single "Mountain" 4-8-2 locomotive in 1923. It was assigned road number 4700 (later is was renumbered 6699) and was designated Class M1. It was a common practice for the PRR to build a prototype that could be tested thoroughly before ordering more of a locomotive design.

The M1 series was also known to be the receiver of several different tenders. Each new tender was an improvement in size and capacity, with the largest being the 16-wheel PRR model 210-F-75B tenders, which were nearly equal in length to the locomotive.

Apr 1, 2011 · #6755 is an M1b class Mountain type locomotive (4-8-2) built as an M1a by the Pennsylvania Railroad at its Juniata work shop in Altoona, PA, in 1930. The prototype for the M1 class was built by the PRR in 1923.

Now famous for their beauty and performance, Third Rail is bringing you the M1a and the modernized M1b in 100% lifetime brass detail. One can still see the M1b in the PRR Museum in Strasburg, PA.

PRR No. 6755 was built in 1930 and ran until 1957, when the Pennsylvania Railroad retired all of its remaining steam locomotives. Click on the ad for more information. Please report objectionable advertising to the Editor. 1953, No. 6755 was rebuilt from a class M1A to M1B.

Sep 20, 2018 · My books list the spotting difference between the M1a and the M1b is the solid pilot of the M1b. However, I've read that several M1 and M1a engines also got the solid pilot.

M-1s remained in service on the PRR until 1957, when steam was phased out on the line. An M-1 is currently on display at the Railroad Museum of Pennsylvania, and was added to the National Register of Historic Places in 1979 as Locomotive No. 6755.