The picture is of a class A87 works car from Oslo, Norway. Built in 1987 by coach/bus body builder Vestfold Bil & Karosseri in Norway to specifications by Oslo Sporveier. The trucks come from former Gothenburg class M23 cars, that Oslo bought back in the late seventies/early eighties to cope with an acute shortage of trams.
The works car, here ploughing snow (with an add-on plough made from a plough attached to an old truck, with added weights giving the plough a total weight of about 5 tons. It (the plough) thus has to have its own brakes, and those & the "wings" on the plough are operated by compressed air fed from the works car.). The whole thing attaches mechanically using standard Oslo coupling gear ("Albert" bolt couplers). Air is fed through hoses.
Place: Holtet station/workshops/sheds - January, 1997
This picture and information kindly provided by Peter Udbjørg