If I want to convert older Bachmann or Atlas cars from the 70's and 80's to knuckle couplers, how would I know if the replacements are 40, 50, 70, or 100 ton roller bearing trucks? I want to make this as easy as possible without just changing the couplers to micro-trains. Also do couplers from different manufactures work together well? Thanks for your help. Paul
Generally speaking, roller bearing trucks only come in 70 ton and 100 ton versions (although Kato does make a 125 ton roller bearing truck for their well cars). Most cars built from the 60's forward use 70 ton trucks. 100 ton trucks would be used on extra long or high capacity cars.
Micro-Trains, Accumate, McHenry and EZ Mate are probably the most common non-Rapido couplers in use these days. They all get along just fine.
-Mark
Thanks Mark, that's exactly what I was looking for.