Never done it but i leave mine in the car with the windows up and car running. Remote start baby.. Crank up the AC, lock the door and by the time i get back in, i have to turn the AC down some b/c its almost too cold in there. Major isn't panting in the least when i return. Ive almost broken a car window before for a dog, but as i was contemplating it, the owner came back to the car and left. No idea how long the dog was in there. Couldve been 3 min, couldve been 30.
I live in Australia, before I moved I lived in a regional area, where it would easily hit 45 degrees Celsius outside, let alone in the car. I can barely stand it for ten minutes before I open a door to let air in. I have NEVER and will NEVER leave my dogs in the car on a hot day. Why would we do something to animals that we wouldn't do to a human child? This guy is amazing for standing that for 30 minutes. People need to learn... Poor pooches can't handle it, and nor should they.