iki/Union_Pacific_Railroad" title="Union Pacific Railroad">Union Pacific</a></td>
<td>X4000-X4024</td>
<td><a href="//en.wikipedia.org/wiki/American_Locomotive_Company" title="American Locomotive Company">ALCO</a></td>
<td>1941-–44</td>
<td>Steam</td>
<td><a href="//en.wikipedia.org/wiki/4-8-8-4" title="4-8-8-4">4-8-8-4</a></td>
<td>548 t</td>
<td>6,290 <a href="//en.wikipedia.org/wiki/Horsepower" title="Horsepower">horsepower</a> (4,690 <a class="mw-redirect" href="//en.wikipedia.org/wiki/Kilowatt" titl