These trucks are of a German design that, in North America, were only used with the original Superliner I cars. They were originally equipped with an air bag suspension system, but that system was soon found unsatisfactory and the bags were replaced with springs.
Kato makes the only N scale trucks in this style (for their Amtrak Superliner I Cars) -
Kato catalog #800071 (Superliner I Passenger Truck, Black w/ Automatic Coupler, 1 pair).
Kato catalog #800073 (Superliner I Passenger Truck, Silver w/ Automatic Coupler, 1 pair)
