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[quote user="BroadwayLion"]According to the Specs is is an A0 A0 + A0 A0 or some nomenclature similar to that. One motor per pair if I read that correctly, probably the inboard wheels with the outboard wheels of each truck being for weight bearing and tracking.ROAR[/quote] Lyon, I think you are right that the locomotive has a total of four traction motors.  The builder calls the wheel arrangement 20 + 20 – 20 + 20.  I think we would call it A1 + A1 – A1 + A1.  However, I wonder if that actually truly indicates which axles are powered.  Their designation may actually be referring to what would technically be called 20 + 02 – 20 + 02, or 02 + 20 – 02 + 20 (depending on what axles are powered). In any case, it is not D-D wheel arrangement.  I interpret the stated wheel arrangement to mean each end of the locomotive is supported by two 4-wheel trucks with one axle of each truck powered and the other an idler axle to carry and distribute part of the weight.   The large prominent beam appearing on the side of this double truck complex is the side beam of a span bolster.   I assume that both side beams are connected together with cross pieces, but those are hidden from view.  The entire span bolster pivots horizontally on the bolster pivot boss of the locomotive main frame.  Then each of the two 4-wheel trucks have truck bolsters that pivot horizontally on the pivot bosses of the span bolster.  It seems to me that this is going one step beyond the A1A-A1A wheel arrangement and adding one additional idler axle per truck.  But this takes it beyond the curve-negotiating ability of a rigid 4-axle truck frame, hence the double trucks and span bolster.  That explanation is what first occurs to me, but I cannot be thoroughly convinced by what I see.  I would not expect to see the span bolster having two sides that are outside of the trucks.  I would expect the span bolster to be hidden between the truck frames.  And the big side beams of each 4-axle set taper down to a point at each end.  That would seem to preclude any structural cross piece connecting the ends of the side beams.  Moreover, the side beams are loaded directly at their tops apparently directly from the locomotive side sills.  That would preclude the side beams from being a part of a bolster that pivots horizontally.  So I am a bit nonplussed.
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