2011 GMC 3500, 15,000 miles. 'three weeks ago DEF message, went away before I could read it, something about exhaust ..... see owner's manual. Message went away but engine light on. I filled with DEF, CEL light remained on for a few days then went out. All good, or so I thought. Next came DEF quality poor. That too went away after a few days. Then just two days ago the CEL came on again, no message, still on. I can no longer trust the truck. From the same GMC dealer I have bought 4 vehicles, a 2004 Yukon, 2004 Sierra 2500 (gas), 200t Sierra (gas), and this 2011 Sierra 3500 D-Max. I can't risk DEF problems causing me to limp when I'm 1,000 miles from home. I loved the truck until now, but it will soon be replaced with a RAM 3500 and, yes, a manual tranny.
Took delivery 3/15/2011: Red LML Dually, CCLB, 4x4, SLT
Previous trucks: 07.5 GMC 2500 CC 4x4 6.0 gasser04 GMC 2500 CC 4x4 6.0 gasser, 2000 F350 SC 4x4 6.8 gasser, 97 Explorer 4x4, 73 Ford tandem tractor 290 Cummins, 62 GMC pickup, 62 Chevy pickup, 53 Ford pickup and another 62 Ford, don't remember model - was large dually with aprox 16 ft. box