I also have a 18' open. I have the 10,000 lb straps too. BUT, I wouldn't recommend tying the car down like this {see attached}. I want to get axle straps and D-rings installed. The hooks on the end of these straps are hooked on the bottom side of the trailer, where the ramps hook on. I have ruined 2 straps. They get frayed easily. I crossed the front straps. These ones are a little long, as you can tell. I bought them the day before this trip. It'll def. be different this year.