It's not just the trip pins that are catching, it's the whole bottom half of the coupler!  I haven't measured the wheels on the 44 tonner, but I believe that they are only 30" (scale) whereas everything else is 36".

My Spectrum HO 44 ton switcher hangs up on every turnout and rerailer on my layout. I am using code 100 track throughout.  The wheels seem to be a smaller diameter than all my other locos and rolling stock thus putting the shell closer to the track.  The Bachmann clone kadee type couplers will not cross any turnout.  Has anyone else experienced this?  Other than raising the shell, how do I fix this problem?  Even at that, the bottom of the trucks still drag across the rerailers!