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Truck started having issues, diesel exhaust fluid quality
Truck started having issues, diesel exhaust fluid quality low and throwing p20EE code for NOx sensors, replaced both sensors, didn't solve the issue, removed def injector and cleaned it's opening in t… read more
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We had a message on the DIC that read def was getting low,
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2011 GMC Sierra p205D and U029D looked over wiring found no bad connections or bare wires … read more
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2011 GMC Denali Sierra 2500. DIC informed of need to service
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Eric
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I have a GMC with a 6.6 duramax, I have a “speed limited to
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I have a 2011 GM Sierra 3500hd with the duramax lml engine.
I have a 2011 GM Sierra 3500hd with the duramax lml engine. I have a service exhaust message and another that says on next fill up I will be limited to 4 MPH. I think the problem is the reductant heat… read more
Gm Tech (Cam)
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Second opinion] 2012 GMC Sierra DIC buttons dont work. … read more
Chris (aka-Moose)
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I have a 2016 gmc diesel I got a warning light-to Service
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My 2011 Denali is a piece of crap, the def fluid sensor won't go out, check engine light on, what moron designs this junk? 50k$ truck is crap … read more
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Second opinion] 2012 GMC HD Duramax. Intake pressure is
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Fault code P21AB, P21AB Reductant Level sensor circuit high,
Fault code P21AB JA: Just to clarify, what's the exact code? And have you tried to reset it? Customer: P21AB Reductant Level sensor B circuit high JA: What is the model/year of your GMC? Customer: 201… read more
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I spend a lot of time on the road. i am retired. i usedto
I spend a lot of time on the road. i am retired. i usedto design and build 12V and 24V control systems. This winter my DEF started giving me strange readings. the tank was at 14% and it took maybe 1 g… read more
Expert
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2012 GMC Denali HD 6.6L diesel. Engine light came on. Got
2012 GMC Denali HD 6.6L diesel. Engine light came on. Got code P2BAD, NOX Exceedence-Root cause unknown. What is that all about?… read more
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Meet the Experts:

Gm Tech (Cam)

Gm Tech (Cam)

GMC Mechanic

31,720 satisfied customers

GM Grand Master Technician 2007. 14 year experience.

Gary

Gary

ASE Certified Technician

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Dave Nova

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929 satisfied customers

ASE Master Certification. GM World Class Certification

Chris (aka-Moose)

Chris (aka-Moose)

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JFN1

JFN1

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Don - Mo Lurch

Don - Mo Lurch

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GM, GMC, Chevrolet Cert., Heavy Line Mech, Race Shop Owner, Mobile Electronics

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Mike S.

ASE Certified Technician

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GMC N.A.I.S.E. Certified Auto-Mechanic

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