Check the listing for details. Conoco Nth Motor Oil 1948 Tractor Trailer Ertl Diecast Bank Limited Edition. Color: Multi-color, Condition: New. Listed at 19.99 USD. “B”. The Conoco Nth Motor Oil 1948 Tractor Trailer Ertl Diecast Bank Limited Edition is a collectible advertising item featuring a multi-color design. Produced in 1992, this original piece showcases the theme of gas and oil, with the iconic Conoco brand displayed prominently. The limited edition diecast bank is a unique and nostalgic piece for collectors interested in vintage gas and oil memorabilia.“B”. The Conoco Nth Motor Oil 1948 Tractor Trailer Ertl Diecast Bank Limited Edition is a collectible advertising item featuring a multi-color design. Produced in 1992, this original piece showcases the theme of gas and oil, with the iconic Conoco brand displayed prominently. The limited edition diecast bank is a unique and nostalgic piece for collectors interested in vintage gas and oil memorabilia.