History of Bacahmann G Scale Trucks and Wheels

[jviss]

I would love to know the history, the models and chronology, of trucks on Bachmann G Scale trains.

I just bought a few N.O.S. G Kit passenger coaches, and they came with passenger trucks, of course, and plastic wheels, with the knuckle couplers installed and the optional hook and loop couples. 

After researching these online I have come to the conclusion that these are identical to LGB 67380 trucks - I mean, like they came out of the same mold!  I'd like to know how that happened.

Also, I tried putting Bachmann metal wheels on them, the G81011 that comes on the Anniversary tenders, and the brake shoes rub, with too much friction to work.  The Bachmann J&S passenger trucks have metal wheels, and I was wondering if they were smaller diameter. 

Anyway, would love to know how many different trucks were made, and the chronology.

Thanks,

jv