If the washer is spinning, even slowly, then the problem is not electrical such as a lid switch and there can be several mechanical problems that can cause a poor spin.
The water must drain out quickly enough to allow a spin. Check the flow of the water in drain and make sure the water is draining out completely. There where some know issues with this pump moving the water fast enough to allow a good spin.
If the water seems to be draining okay then check how fast the basket spins empty. The belt must have proper tension to spin the basket with a load. The motor pivots back and forth with a spring to provide proper tension to the belt. This can be tricky to check because with a tub full of water the belt is suppose to slip so the tub doesnâ€™t spin fast until most of the water has drained out.
The basket must spin evenly. If the basket is leaning to one side then in spin it may not be balancing itself to enable a fast spin. Make sure the 6 suspension springs are okay and none are broken.
If the washer is loud in spin as you describe then the spin bearing can be the cause of the poor spin. A bad spin bearing will not allow a fast spin.
The bearing is a part I'd recommend a technician repair. It will require removing the transmission to repair and the repair cost may be close to the replacement cost.
To check the pump, motor, belt and suspension springs you will have to remove the front and rear panels from the washer. The image below shows how to do this. Remember to unplug the washer first before removing the panels.
The image below also contains a trouble shooting guide for a slow spin problem. If every thing you check seems okay then the spin bearing is the most likely cause of your problem.
I hope this information helps to resolve your problem but if the checks bring up more questions than answers then submit another question with any additional details for further assistance.