Saggy rear end..
 

I have a 1997 e320, (W210) I sometimes pull a trailer, (light sport aircraft) less than 1000lbs.
Is there any way to get the rear end of the car back up? The car hauls the trailer just fine, but the extra tongue weight really mashed the rear down, and it wears the tires on the insides. Does anyone make an air bag or air shock that would work for towing? Thanks!