My mind has been a lot on dogs lately because our old dog died and I am looking for a buddy for our younger dog. Anyway I wanted to share an idea with those of you who have big dogs that may eventually have a problem getting into your vehicle. Harbor Freight (for one) sells a light weight folding aluminum ramp made for loading lawn tractors, MC, etc. When they are on sale they cost about $50. You take them apart and have two sections that look like ladders. We cut a piece of 1/4 plywood and fasted it on and covered it with carpeting for traction. It is completely sturdy with no sway so the dogs are secure walking on it - and if you want you can make another one with the other half and probably sell it for more than you paid for the whole thing! It is light weight and easy to lift and stow.