Clunking noise in rear when accelerating

the "backlash" felt by reversing the drive shaft direction is normally the clearance in the spider gears in the diff so to get rid off that ( not necessary unless it is excessive) is to pull the diff center out and fit new thrust washers behind the spider gears
next check the diff mount bushes as the diff reaction will move the bolts in the mounts and make the noise

check the u joints

If it is a four wheel drive check your tail shaft or drive line by securing the vehicles front wheels jack up the rear tires and in park try to rotate the drive line if you can hear the transmission sound like it is going into gear the transfer case could be damaged! If not a four wheel drive pull the transmission dipstick and look to see if the fluid is dark red or metallic grayish color if so then you're clutch disks inside the tyranny have been worn out and it needs to be rebuilt!

Jack the vehicle up by the pumpkin and use kickstand to support. Turn the wheel back and forth and you d should be able to isolate. It sounds like a gear in reared or wheel bearing

check the sway bar links

it sounds like a transmission prob or break or suspension

I would start by replacing U-Joints. They are really common issues when it comes to clunking noises. I'd start there.

Sounds like a bad cv joint. Easy way to check is to raise the front of the vehicle so both front tires are off the ground. Use jack stands under the vehicle and block the rear tires. Start the engine and put the tranny in drive. Let the front wheels rotate while the engine is idling and turn the steering wheel slowly in both directions. Listen for the clunking noise. You may have to speed the engine up a little to make it work.

its a wheel bearing. .will need to be inspected to determine the correct one. Also tires could also do this if the steel seperated internally. Rotate the suspected tire to see if it follows the tire.

usually the knocking is the drive bearings, or, the shock absorbers...so , i would check the shockers, if your wheels are rotating normally