MELGAR,
I always look forward to your posts.
What was the reason for using flexi oil trucks?
Did the flexicoil trucks track better on uneven tracks?
Here is my BOSTON & MAINE SW1 pulling a NAUSET MODEL RAILROAD CLUB Weaver PS-1 boxcar. (Sharp eyes will notice my custom designed KADEE high rail couplers that I have installed on most of my rolling stock.)