Talk:EMD DDA40X

Strongest engine ever built or strongest _diesel_ engine ever built?
There are stronger electrical engines in operation today, e.g. on the Swedish Iron Ore Line from Kiruna to Narvik. So obviously the statement is incorrect in its current form. At most it is the strongest diesel engine ever built. — Preceding unsigned comment added by 93.244.142.29 (talk) 08:16, 20 August 2017 (UTC)

DDA-40-X vs. DD40-X
The DDA-40-X Model Designation was created by EMD and used in officially sanctioned maintenance and operating manuals. For example, I have in my possession a 1970 copy of the DDA-40-X Maintenance Manual. However, the UPRR Loco Dept. has preferred to use the DD40-X model designation in all official literature and maintenance records since they began to arrive on the property in 1969. Electrical prints, annual diagram books and LMIs (Locomotive Maintenance Instructions) throughout the 70s and 80s all use the DD40-X designation. This model designation is still in use at UPRR; the maintenance records and UMLER file for the UP#6936 continue to use the DD40-X designation. Sunktanka (T:C) 05:48, 3 January 2007 (UTC)


 * Generally, we use the manufacturer's official name as the title of an article, but add redirects where appropriate. Since this model was really used by only the UP, this information should be mentioned in the article too. Slambo (Speak)  11:33, 3 January 2007 (UTC)

#70-80?
Where there ever any DD40's numbered between 70-80? Because i've seen a model version and its either number #78 or #76.User:Trainboy 02:31, 7 March 2008 (UTC)


 * No, there were no DD40X's numbered between 70 and 80. The locos you are thinking of are DD35A's which were numbered between #70 and #84.  There were also cabless versions designated as DD35's that were numbered from #72B to #98B.  Sunktanka (T:C) 10:47, 17 March 2008 (UTC)


 * The model versions you saw were by Athearn (HO scale) and were based on preliminary plans from EMD. The preliminary plans were very similar to the appearance of the DD35A, so the model is really a slightly incorrect version of the DD35A, altho Athearn still (iirc) refers to it as a DD40 (not DDA40X). Bachmann made a HO scale model that is more representative of the DDA40X.Ken (talk) 14:21, 19 September 2008 (UTC)

Anyone else?
Did any other rail-road use this double engine technology?.User:Trainlover 02:34, 5 March 2008 (UTC)


 * Most center cab locomotives would have two engines in them, though they are usually much smaller than the DDA40X. n2xjk (talk) 18:18, 18 March 2008 (UTC)


 * Previous to the DDA40X, (in the DD35 timeframe) ALCO produced a double engine C-855 and GE produced the double engine U-50. The U-50 and the DD35 were used by Southern Pacific as well as Union Pacific. Over the years, double engines have been used often; a very popular example is the EMD E-series of passenger locomovives in the 40s-50s, and were in use thru the 70s. Ken (talk) 14:25, 19 September 2008 (UTC)


 * Baldwin produced a single prototype of a cab unit that was designed to contain 8 v8 diesel engines, only 4 of which were ever installed. There was also a center cab (Davenport) which used 4 engines, 2 in each end. (per Pinkepank's Diesel Spotters Guide) These were rare and usually 1 of a kind products, some would say mercifully..... Ken (talk) 18:28, 10 December 2008 (UTC)

changed pic
I changed the article pic to one that more clearly shows the outrageous length of the unit. Ken (talk) 18:46, 18 September 2008 (UTC)

It's DD40AX
From every source I have seen, EMD called these locomotives DD40AX, not DDA40X. Bclough (talk) 01:57, 20 September 2008 (UTC)


 * I have in my hand a copy of the DDA40X Maintenance Manual, published by EMD in 1969. I spent several years in the UPRR Loco Dept and, during my tenure, observed numerous EMD publications (above & beyond my copy of the mtce manual) that utilized the DDA40X designation.  The UPRR Loco Dept, however, has always used the DD40X model designation. Sunktanka (T:C) 09:42, 15 November 2008 (UTC)
 * My copy of the EMD "Master Parts Catalog", also references this locomotive as DDA40X. Wuh  Wuz  Dat  02:01, 24 January 2010 (UTC)
 * PDF copy of EMD operators manual here lists model as DDA40X. Wuh  Wuz  Dat  02:22, 24 January 2010 (UTC)

DDA40X Nicknames
I recently took part in a discussion on the Model Railroader (magazine) Forums. A forum member linked this article as a source for the "Big Jack" nickname of the DDA40X. A retired UP employee on the forums stated that he had never heard of that nickname being applied to the locomotive. I investigated the linked resource material. No reference was made to "Big Jack" as being a nickname. As a result I added a citation needed after the "Big Jack". I could not figure out how to edit the side bar on the right, which also contains this info.Robert Almart (talk) 20:23, 13 February 2017 (UTC)

Surviving models
Is there no source for the info about how many are left and where they are located. No date on that info either 71.47.103.160 (talk) 15:24, 18 July 2018 (UTC)