Loud banging/thumping during spin cycle on my kenmore front load

Most likely tub bearings and spider gear are bad.

Most noises from a washing machine occur during the rinse or spin cycle. If you hear loud thumping during the spin, the load of clothes may have become unbalanced. Stop the washer and redistribute the clothes, then re-start it. Repeat these steps if necessary.This will solve your problem.

If you spin the drum by hand, does it make any kind of thumping or banging noise? If it does, then you probally have a broken spider arm(s). This is very expensive to repair, unless you are handy, it may not be worth fixing. The link below shows the problem and how it can be fixed.
http://www.jimwilliamson.net/misc/2006-08-28-front-load-washer/index.html

Could be a broken spring on top of the drum allowing it to hit back of casing...hope you fix...

Need more information to make an accurate diagnosis, try removing the front panel (two screws at bottom) and visually check first the belt (all the way around) and then the springs that hold the tub suspended.
I would bet on the belt.
Quentin

Here's what the problem is. 
http://www.youtube.com/watch?v=UwpKP_9_fAA&feature=player_embedded

It's been designed to fail so that you buy an expensive part. 

please balance your washer and use smaller loads

make sure all shipping pins are out the tub should move all around from side to side if it level still bangs its eather the balance ring top basket are there 3 slides on a plate above the motor just put some silacone oil on tham move around

Be certain that nothing got under the rubber skirt, pull it back and look /feel under it .
inside the tub are the large wiper arms solid and not come loose.
open the top access panel (3 screws in top rear )
and open the bottom access Panel (3 screws in bottom front)
Dissconnect power .
Look at the springs and arms that attach to the tub are they secure.
is the large stone concreate slabs secure.
move all these items and push at them all secure?
you can run it while open but the bottom has a switch on front right that has to be closed.
look watch listen.

washing machine making noise, remove water but doesn't spin