I have a 06 Ford F350 diesel 4x4 crew cab long bed(not a dullie)with 7000 miles.My front end is sagging enough that when i hit bumps in the road i bottom out on the bump stops.I have taken it to the dealer and they said there wasn't anything wrong with it.When sitting on level ground my front bump stops measure 2 3/4 inches.Just wondering if anyone else has had this problem and how they fixed it.

You can go to a spring shop and get new coil springs installed. This is fairly expensive but will solve the problem.
You can try air shocks which will help some.
I don't know how you drive but think ford installed poor springs and should warranty them.