1137 has received new traction motors, dynamic brakes, HEP, and a bunch of other mechanical components. It is still not finalized if it will be in MassDOT blue, but in quote from the assistant project manager down at Rochester, "People seem to like to blue paint on 1136 so we are hoping to do the same for 1137."
FYI 1139 is getting the same upgrades as 1126 did. There’s an insider video on YouTube supporting that answer. You can figure it out yourself because I’m not going to reveal the person’s name in consideration of privacy and job confidentiality. The only difference with 1139 compared to 1126 and 1120 is that it’s getting a new horn. Even though that isn’t really considered an upgrade, it’s interesting to discuss about that stuff. Does someone want to confirm if 1126 got repainted or not? I know 1120 didn’t receive much other than the internal upgrades and an ebell.