I just purchased a 2020 Tahoe Midnight Edition on Saturday, 01/11/2020. Drove it about 2 1/2 hours on Saturday, 1/18/2020, after a good nights rest. We hit the road around 9:00 a.m. Husband and I both got very sleepy on the trip. After visiting family for about 1 hour, we got back in the Tahoe and started home. Again, husband got sleepy so I took over drive. This was around 2:30 or 3:00 pm. He feel asleep and I started getting sleepy too. We stopped and ate lunch in an effort to wake up and walk around. I don't remember much after that until I woke up off-road and fighting to gain control of the vehicle. I had fallen asleep at the wheel at 3:30 in the afternoon while my husband was asleep in the passenger seat. We traveled about 450 feet, hit three driveways (airborne after each driveway) and I was able to get it stopped just short of the wood line. Fortunately - no one was injured (except my Tahoe). I fear there may have been a carbon monoxide issue with the vehicle as this occurred in the early afternoon and we were both extremely sleepy while in the car. Heater was on, windows rolled up. Impaired judgement, drowsiness. Took us both a few minutes to get our bearings once we got out of the vehicle. Has anyone else experienced anything like this? My Tahoe is now at the body shop getting repaired and I have asked them to check the emission system.