Looking at a 2003 Chevy 2500HD crew cab with the 6.6. Has 242,000 miles, has Banks equipment(not sure but think exhaust, the Banks power IQ, and possibly a chip) also has aftermarket open intake system with a cone shaped filter. Took for a test drive lots of power no obvious problems other then when I matted it it would lay out a huge black cloud basically until it shifted out of passing gear. This was at normal operating temp. No power loss or hesitation would set you right back and wanted to hop and break the tires loose on pavement as the tread is very little. No clue of any maintenance yet as far as injectors etc. Price is 10,800. Any thoughts?