My dad grew up in Letterkenny in Donegal. His dad had a small farm, and also the franchise from Esso to supply oils and fuels locally, and he talked about a similar horse-drawn fuel tanker.
Dad told a tale of the said tanker being loaded on a flat wagon of the Londonderry & Lough Swilly railway and it overhung the sides, but was judged safe to travel. At a subsequent station, the hub of one of the wheels ran up the platform ramp, and the wheel spun furiously, as you might expect. it clearly made some impression on him
I don’t know how old he was when this happened, quite young I suppose, I’m guessing were talking 1935 or so.