See posh car shunting into railway truck (5)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Seems to be Lo(=see) + R(=posh car) in r{ailwa}y. I would have expected posh car to be RR for Rolls Royce, so I don't know if this is an alternative abbreviation or refers to some other posh car.