Tips on changing lanes

I have found that when pulling our 38' 5th wheel that after signaling a lane change for a little while I start moving into the new lane. Amazingly others seem to get out of the way! Phoenix drivers are the worst, they tend to speed up from behind when they see me signaling to change lanes. They are a bit surprised when I start moving into the lane I was informing them I was going to move into. Being a little aggressive seems to work better than trying to be nice to everyone. The right lanes on Phoenix freeways end at the next exit so one has to change lanes or end up on an exit. So I have learned to immediately move a few lanes closer to the fastest lane to avoid getting caught having to make a forced lane change.