2018 GMC TERRAIN Structurebody Problems

The strike plate on my rear driver door fell off. The plate and bolts are in perfect condition but the backing is gone. Multiple body shops have attempted to locate the backing, which is somewhere between the interior and exterior metal body pieces, and gave been unable to. Every body shop I've taken it to also says that they have never seen anything like this happen before. They are reluctant to fix it because that would mean cutting through the body to replace the backing for the strike plate then welding, sanding, and painting in the area they cut and they worry about the integrity of the striker and functionality of it as well, as they've never had to do a repair like this before. One of the body shops was also a certified GM repair shop at the dealership from which the car was purchased and even they have...

Rear side windows in hatch area leaked filled up spare tire compartment with about 3-4 gallons of water. Now navigation doesn't want to work, sunroof not working, electric systems are not working right

I PULLED INTO OUR CARPORT. IT FELT LIKE THE CAR JUST "SPED UP AND WENT FASTER AND FASTER." IT HIT THE FRONT OF THE CAR STRAIGHT ON. NO AIRBAGS DEPLOYED NOR DID THE FRONT END COLLISION STOP HAPPEN.