OK, so first things first, got the go ahead from the Bank so I am full bore shopping for my first Diesel now!

So I am looking at late 2000's (2003-2009) Cummins Equipped trucks! I'd like to find a gear jammer but would take an Automatic if it's nice and the price is right!

Anyway Just wanted to know what are some thing to check for when shopping around for Diesel Trucks? Brand specific or otherwise!

Also one of the first mods I plan on doing, (Besides an intake and Exhaust) is a Tuner or a Chip! Was wondering what the difference is between Chips/Tuners, and also I've heard a lot about people having a tuner specifically programmed for their vehicle? Is that a requirement? Or am I just mis-reading something? And if so where can Someone get that done?

Thanks for the advice!

Respectfully,
Austin