Until 2004, regional services were provided by locomotive-hauled trains.
Push-pull is a mode of operation for locomotive-hauled trains allowing them to be driven from either end.
Following major repairs the weight restriction was relaxed in 2005, and locomotive-hauled trains have again been allowed to cross.
At first, locomotive-hauled trains of Silberling coaches operated on the line.
The new cars would purportedly have saved $4.25 million over three years, being four times more fuel efficient than a locomotive-hauled train.
However, some locomotive-hauled trains may contain more than one power unit and thus be able to continue at reduced speed after the failure of one.
The running-around line between these two, for locomotive-hauled trains, still exists.
In the late 1990s, the locomotive-hauled trains were replaced with class 628 diesel multiple units.
The results so far include eight diesel cars, two locomotives and five locomotive-hauled trains, all of which are being refurbished.
These changes meant that there are no "run-around" facilities, making it difficult to operate locomotive-hauled trains on the line.