When I take off and turn in forward there is a loud knocking or popping sound from the rear of the truck. Kinda scary sounding like something gonna break or twist off!!! Took a look underneath and everything seems ok. (u-joint and no leaks from diff) Not sure what the heck it is. It's only doing this when taking off, once going down the road everything seems fine.

2005 scab 4x4 w/70,000 miles

Thanks
FLY

 

The rear wheels both have play when I push them, I can hear them move. The lugs are tight. I guess it's the hubs?

 

wheel bearings are bad if they move up and down, but would not cause any loud clunking. if you have a trash lok it could be it making noise and sloppy wheel bearings make it exagerated. replace the wheel bearings and inspect the differential while your in there.