Is it possible to retrofit Bachmann trucks with knuckle couplers to other brands of rolling stock---or conversely, can Bachmann rolling stock be retrofit with NMRA "N" scale couples & trucks?
I'd start with Micro-Trains' 'Universal Coupler" packages 1128 (Short Length Shank), 1129 (Medium Length Shank) and 1130 (Long Length Shank). They're economical and you get two pairs per package. When assembled, the parts are placed in the pocket which once occupied the Rapido coupler and spring. The work can get a little fussy, but you'll get the hang of it. I converted most of my cars using these. You can otherwise just replace the trucks and gain the M-T coupler conversion that way.
There is no NMRA "N" scale coupler, the defacto standard coupler in N is the Micro-Trains knucklet coupler.
As Hardcoaler stated the T shank series of MTs can be fitted depending on the length needed. The last time I dealt with any Bmann cars they used a screw to mount their trucks with the cars equipped with a metal underframe. I mounted MT trucks on them by using a sharp pointed exacto knife or a small round file to slightly enlarge the MT truck mounting pin holes so the Bmanns small screw could be used to mount the trucks.
I have replaced all my Bachmann steam locomotives' couplers with the Atlas couplers. They are drop in, and look much better.
