From Greenbrier's website:

Greenbrier Leasing Company LLC (GLC) owns and manages one of the largest railcar leasing fleets in North America.

Railcar Types:
GLC proudly owns and manages numerous car types which serve a multitude of market segments vital to the industries and economies of North America, including:

Small Cube Covered Hoppers: cement, sand
Mid Cube Covered Hoppers: grain, fertilizer
Large Cube Covered Hoppers: plastic pellets, DDG
AAR 211 Tank Cars: vegetable oils and unregulated commodities
DOT 111 Tank Cars: non-flammable chemicals
DOT 117 Tank Cars: flammable and hazardous products
Pressure Tank Cars: liquefied petroleum gas
Boxcars: paper, appliances, pulp, forest products and panel products
Gondolas: scrap metal, copper concentrate
Intermodal Cars: containers, trailers
Auto Racks and Automax
Centerbeams

GLC acquires the majority of its railcars via new production from one of Greenbrier Manufacturing’s world class production facilities. However, GLC has been and will continue to be opportunistic when acquiring cars through the secondary market

[www.gbrx.com]