I had a friend puppy squeeze halfway out a 6"opening in the back window...i looked back and saw her and grabbed her back legs....i was doing 60 on the expressway!

 

My AmStaff/American Bulldog mix jumped out of the back window driving down a road. He has a pretty strong prey drive and this squirrel was too tempting, and overrode common sense. Had some good road rash on his legs and a nasty one on his chin. Luckily we were going on a 15 MPH road. Now windows only go half down. Funny part is, after his barrel roll, he shook it off, and bolted after the damn thing.

 

Same here. Strap to the middle and give only enough slack to look over side not climb over it!

 

My one Boston terrier was sitting on my lap in my jeep while I was waiting for my buddy to come out of his house. Doors were on and window was down when she saw his cat and jumped right out my window and started chasing it. It was amusing, i'm surprised she did that considering she's scared to walk down steps lol

 

X2, Dog loves the air and I love peace of mind.

 

I would definitely recommend a harness of some type. I will be purchasing something for my dogs as well. An unsecure pet is just like an unsecured passenger when something bad happens like a wreck or rollover. I worked a rollover accident last week and a dog was ejected. Sad deal. Made me think twice about taking my pups with me on roadtrips. Plus with a harness you wont have to worry about a jumper.