07-21-2010, 06:47 AM
The gray unit is indeed a remote control paltform. It is a retired GE unit, no fuel tank and unpowered. I think the traction motors are still in place but it is not a slug. It is used to remotely control whatever consist is M.U.ed to it. The others are GP15/GP38/GP15. At least one of them is now owned by Helm Leasing (HLCX). The Up roster is so large that they found it made room for more units to use different reporting marks on yard power, hence the UPY 129, or UP Y129.
-Dave