I have a 2011 Outback with trailer hitch. Been looking at pop-up campers. Reading my manual, I see that trailers without brakes should weigh less than 1000 lbs. When we bought the car I was just told that towing capacity was 3000 lbs. No mention that no trailer brakes limited towing capacity. Anyone towing a trailer without brakes weighing 2500+ lbs.? Is it really unsafe or damaging to transmission/engine?