The GTLW DAT45AB (DAT meaning Diesel Automatic Transfer, 45 referring to the 4,500hp, and AB referring to the two units) was a 1996 joint-rebuild of both the failed 1994 GTLW DAS16 (DAS meaning Diesel Automatic Switcher, and 16 referring to the 1,600hp), previously CGTR #75 and a GE U25C, previously CGTR #3721, which was well-known from helping clean up the Houston Ammo Train Incident in 1979. The 2-axle DAS16 would be rebuilt into a 4-axle A Unit, and the power output would be upped from 1,600 to 2,000, while the U25C would be rebuilt into a B Unit, with the only difference being the removal of the cab and the engine bay’s height being reduced. These locomotives would be specifically tailored to be used as transfer locomotives for a rough journey between two key yards on the Central Gateway Turtle Railroad, often used to transfer rolling stock to the local shortline. The DAT45AB would be numbered CGTR #77, and CGTR #76 and #75 would become two new DAS25s to replace the DAS16s' original function, however with the ever-growing importance of the yard the original was going to be in, the horsepower would be upped. #75 would operate the originally intended yard of the DAS16s, while #76 would be used for switching operations at the two yards, and #77 would transfer cargo between. #76 can sometimes be seen as a trailing unit on #77's trips, so it can perform switching operations involving dropped-off rolling stock from #77. #77 would be the last locomotive to proudly sport the Bluewashed livery, while #76 and #75 would opt for the Hydrogold livery, instead of #75’s original golden ember scheme.