I started playing G089 - Grain - Chicago to Brunswick and it's using two SD40-2 locomotives at the front, with none at the back. Halfway through, the train started going slower and slower climbing up a steep hill until eventually it had no more power to carry on. No matter what I tried, I could never get it to finish going up the mountain. I then looked on YouTube and searched the forums, and noticed that everyone else had an AC440CW for this journey, which makes sense, considering that it has more power to climb those mountains. I wonder if this is a bug or if I'm doing something wrong. I'm playing on a PS4 and TSW2 was updated just a few days ago. I don't know if that changed anything. Thanks for all the help.
This exact service can be selected on the AC4400CW - in fact, any service that leaves Cumberland can be played using either an SD40 or AC4400CW
Many timetable services are duplicated across various locomotives, but it's an unfortunate reality that some appear for locos that aren't up to the task. If you just want to fill out the timetable, you can start with the most powerful loco (AC4400CW) and work your way down.
Did you have the MU valve set to lead or dead? It's possible to get the train moving with the valve in the wrong position (which it is usually set incorrectly by default at the start of the service) but you'll essentially have a lot less power as you'll be fighting the breaks the entire time. Many people often miss a step like this and assume that because the train moves that it's providing all the power it's able to when infact it's severely limited. The valve being in the wrong position is a huge culprit of this Iirc there shouldn't be any issues completing this scenario with the power provided.
I had the MU valve set to lead on the front engine. Isn't that the correct position? I always have to change it at the beginning of every journey. I ended up switching to the AC440CW and that worked without any issues.