I buy dpf system off the big 3 diesel from GM, Ford, and Dodge. If you have any of these systems please message me and I'll help you find the numbers on your systems to determine the price I pay. The numbers given are from the low quality to high quality systems. I'm located in the Ellsworth WI area but can travel to the Madison and possibly Wausau area if there's a few systems that make it worth it. Also buy batteries and other precious metals.