Four packs of freight car models in paint schemes of the Burlington Northern and their predecessors are available at Golden Age of Railroading.
You can choose from a pack of twenty 50ft boxcar models in the colors of BN, GN, NP, SLSF, SP&S and CB&Q, a pack of 55t and 70t offset-side hoppers in BN, GN, NP, CB&Q and SP&S liveries, another pack of 100t hopper cars in BN and NP colors, or a pack of woodchip gondolas in BN, GN, NP and MILW colors.
This is a freeware rerelease of the former four BN freight car packs, with unchanged content over the old TS2013 version: if you already have the old version, you do not need to download and install the files from this page. The models do still work fine in the latest instalment of Train Simulator, TS2015, and do not require any other add-ons or DLC to run.
Find out more by visiting www.golden-age-rails.com