1996 Ford Ranger Rear End Clunking Noise

For the past at least month my truck has been developing a creaking / sqeaking noise in the rear mostly when the truck rocks side to side.
I have been attributing these creaking sounds to the aftermarket spring helpers I have on the truck. ( I really put my truck to work) I thought maybe they were moving a bit and let it go.
As of late though the noises have goten much worse. Not your every so often noise anymore. You can count on it any slight bouce in the road.
So I got under the truck and found that the helpers were still very tight and in place so I shook the truck while under it.
The creaking sound came from the rear end. I got out from under the truck and went and shook the truck by grabing the top of the tire. When I did so I got alot of movement and a clunking sound. So I jacked up the truck and removed the rim and tire then the brake drum.
When I grab the spindle and pull it it will travel in and out about a 1/4 of an inch or so. Give or take.
I dont know if the creaking and the spindle movement are related. I noticed the grease fitting on the plate on and kind of think that may be low on grease and that is where my creaking sound is coming from. But not being more than a guy who can use tools to a fair degree I really am not sure.
I hope I have give enough info and apreciate your help. Thanks in advance Rich