I've filled up my DEF at two different truck stops for my Colorado. Both places required special fleet/truck cards to pay for the DEF at the pump. I didn't have such a card, so I had to go inside, pre-pay $20, pump DEF until full (about $13-15 worth), then go back inside and get refunded the difference.
I filled up at a Loves or Pilot (can't remember which one I stopped into. They were right next to each other) in Colorado and a TransAmerica in Minnesota. No problems with either. Didn't need an adapter either time. Also, the truck hasn't complained once about the DEF that I can tell. Plus it's a bit cheaper than buying the boxed DEF.
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2016 DuraMax Colorado Z71 | Laser Blue | CC | LB | 4wd | Bose | Nav | GearOn Bars | Black Emblems | Wheel Flares | 3" Off-Road Step Bars | Ordered 10/30/15 | Delivered 2/22/2016
Installed Mods: Line-X Bedliner | BakFlip Revolver X2 | Pop&Lock Tailgate Lock | Stubby Jr. Antenna | WeatherTech - Mud Flaps, Deflectors, Floor Mats (Front), Floor Liner (Rear) | @DasGoob-Inspired Flush Stake Pocket Covers and Red LED Bedlighting
Last edited by HeliCarson; 05-08-2017 at 12:48 AM.