ModelRailroadForums.com is a free Model Railroad Discussion Forum and photo gallery. We cover all scales and sizes of model railroads. Online since 2002, it's one of the oldest and largest model railroad forums on the web. Whether you're a master model railroader or just getting started, you'll find something of interest here.
Airbrush for the most part has been my weapon of choice. But on one of the cars I used some weathering chalk.
Why does the site (webpage??) flip photo's on their side. all 3 of these were taking using upright. Two of them display the way they were photographed, one gets flipped.
The cars look good. I don't go much past what you have done. I have seen some really nice heavily weathered cars with rust and other work, but for me I just like them to look like they have been on the rails for a little while.