10.0

really awful
Typical Repair Cost:
No data
Average Mileage:
50,000 miles
Total Complaints:
1 complaints

Most common solutions:

  1. not sure (1 reports)
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This problem may be covered under warranty. Ask your GMC dealer.

problem #1

Jun 022014

Sierra 2500 Denali Duramax 6.6L Lml

  • Automatic transmission
  • 50,000 miles

I have taken it to the dealer in Lewes, De.. could not replicate the problem was my answer. I am now working with another dealership in Dover.

The smoke is from diesel being sprayed or dripping on the exhaust pipes. You can see the stain, but we think it may be causing more issues than just the bad smoke. We now have indicators that coolant is leaking into the heads. (new complaint but I think connected)

Smoke comes out of the rear exhaust more often, not blue smoke more gray.

- Shaun M., Millsboro, DE, US

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