Black and grey tank not emptying completely

We Cant Wait wrote:

Lwiddis wrote:
On the last dump of the trip I elevate the side without the valves by 2 inches using plastic levelers.

I hope you're not in front of me doing that at a dump station. The amount of time you take doing that would just back up the line even more.

Nice comment, unless you are volunteering to do his dumping, he is making a big mess, then you should help them with some advice.
Yes, you should elevate the side away from the dump valves, and if the valves are to the back of the MH, try having the front higher than the back. it is dis-hearting to have 1/4 tank after dumping.