Hi. Don't try to use the mixer anymore, and don't take the planetary off as the problem isn't there. If your mixer is still under warranty, call Kitchenaid, they are good at responding to mixer failure if it's under warranty.
If you're out of warranty remove the single screw to take off the silver band near the top of the mixer. The screw is at the back of the mixer. Next, remove the 4 screws that hold on the top cover. Remove the top cover and locate the transmission housing (it will be a black/gray plastic humpy looking thing) near the front of the machine. Look for cracks in this housing. you can do this without taking it off. If It's cracked, you have found the first problem, and it's a problem that many Kitchenaid owners, including me have had. This plastic transmission housing has no business being in a machine that you paid top dollar for. Their replacement housing is now made out of metal.
A word of warning, and customer service won't tell you this. As managment at Whirlpool Corp. told me. Even if my mixer was out of warranty. they may have repaired it for free, if only I had not taken it apart. So if you've found a cracked Trans. housing, put the cover back on, put the silver band back on and call Kitchenaid customer service. Tell them about your problem. Don't tell them that you took the cover off. They will tell you that because you are out of warranty, all they can do is refer you to one of their authorized repair centers.
If you take it to the repair center, ask for a quote, they will look at it and see the cracked trans. housing, then they will take the housing off and find that the worm gear has been destroyed and possibly the shaft bearings too, they may also find that the bearing seats have been damaged (as in my case). They will tell you about the damage and give you a quote about how much it will take to fix it. Then is the time to contact Customer Service again and demand to speak with a supervisor and tell him/her about the cheap plastic housing and the damage IT caused. Tell them that you want to be reimbursed for the damage caused by this flimsy part. They will argue with you. Ask to speak with management.
If they refuse, contact me at firstname.lastname@example.org
and I may be of further help to you.
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