The "U" does indeed refer to "upgraded". This is not unique to alcos or RS2s. A common one is GP7u or GP9u.
With regards to the RS-2 (and RS-3's for that matter), many railroads re-classified them. For example, the D&H RS-3s became MK TE-56-4A as named by Morrison-Knudsen. The GB&W called their rebuilt RS3's RS20's. The "RS3m" or RS3u" is in some cases a railfan name, rather than a railroad creation. But it depends on the railroad. The CNW had 2 RS-3ms, rebuilt with 251 prime movers and RS-11 hoods, which it called RS-3ms.
Modeling whatever I can make out of that stash of kits that takes up half my apartment's spare bedroom.
cuyama A google search suggests that these were units upgraded by ALCO while owned by the Detroit & Mackinac (thus the "u" designation). Anecdotal postings suggest that they looked more like RS-3s externally. There are literally dozens of photos on-line. D&M RS-2u google image search Successor Lake State Railway RS-2u google image search
A google search suggests that these were units upgraded by ALCO while owned by the Detroit & Mackinac (thus the "u" designation). Anecdotal postings suggest that they looked more like RS-3s externally. There are literally dozens of photos on-line.
D&M RS-2u google image search
Successor Lake State Railway RS-2u google image search
You are probably correct.
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
Thank You.
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SouthPennI wonder if it designates engines built in Canada?
Or, perhaps the railroad's designation that the Alco is MU equipped.
Ed
I wonder if it designates engines built in Canada?
I wonder if the 'u' designation was specific to a particular railroad? It could possibly suggest 'uprated' I believe RS2 were increased in tractive power at a point in their manufacure. It might also mean be 'upgraded'. I cannot find a reference to RS2U. However more knowlegable folks could know the answer.
Alan, Oliver & North Fork Railroad
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If you don't know where you are going, any road will take you there. Lewis Carroll English author & recreational mathematician (1832 - 1898)
I have never heard of a "RS2u", However I found that 347 "RS2" were 1500hp and 31 were 1600hp. Maybe that is the difference. Found nothing on how the hp was increased and external differences, if any.
I keep seeing references to an Alco RS2u. What is an RS2u? I have googled this and all I can find are references to railroads that had this engine but nothing about what the difference is between it and an RS2.
Thanks