Recreational Vehicle Lpg Tank Valve/gauge problems of the 2010 GMC Yukon

The dash is cracked near the passenger side air bag. It cracked again on the part that is over the gauge cluster while driving down the road. The second crack is about 5 inches long, causing the whole dash to vibrate while driving. I epoxy'd the crack so it wouldn't continue to spread, causing the dash to become more unstable.

The plastic dash board has cracked. It started out small coming from the passenger side airbag and stretching to the edge of that dash panel. Now a second part of the dash has cracked by the driver side over the instrument gauge cluster. The portion of the dash that's cracked by the passenger airbag is my biggest concern as it could break off and cause sharp pieces to hit the passenger in the face of the airbag was deployed. My GMC dealer stated my extended warranty doesn't cover this "cosmetic" issue and therefore I will have to come out of pocket for a portion of the cost. This is unacceptable. I'm the original owner and he vehicle is garaged. There could be no long term damage to the dash other than what it's intended to do which is to be under the windshield. GMC - own this issue and correct the problem please. I'm not likely to be a repeat customer of you can't produce a superior and reliable product -or- be responsible and correct an issue that is clearly a manufacturers defect.