Just wanted to share our setup for carrying our 85lb Lab. This is our first new car as a family and we wanted to find a solution for carrying around our large fur child while minimizing the amount of dog hair getting everywhere or scratching up the leather. Its the petsfit collapsible crate on amazon. Dimensions are 36"x24"x23" for LxWxH. It happens to fit perfectly and still leaves room for storing things in the trunk. The crate allows the top to be open too for more space. He's pretty comfortable in it and there is just enough room to turn around while inside even. It folds up in a minute and can actually be tucked behind the 2nd row when folded, but it does limit the reclining ability a bit. Only downside is that it does block the rearview mirror but I expected that and it's folded up most of the time.
https://www.instagram.com/beansthelabrador/
https://www.instagram.com/beansthelabrador/