Loud vibrating/humming noise
Okay...based on the model number, this is a Frigidaire manufactured dishwasher. If you go to searspartsdirect.com and type in the your model number in the Search menu, you will find a useful illustration under the "Motor and Pump" heading. The drain pump is listed as item #60 in the drawing. Before you go through any major dis-assembly, check to make sure the pump is securely in place and not loose. Sometimes the pump comes loose from the mounting bracket and vibrates. Also, sure nothing is laying against it causing vibration noises (I've seen this before). If the solution is not that simple, remove the spray arm assembly inside the dishwasher and inspect all the debris traps under the spray arm assembly. The wash pump and drain pump sumps are located here. Check to make sure there's nothing obstructing the input to the drain pump. Lastly, if all else fails, remove the drain pump and inspect the impeller. If the you've inspected everything and still have the noise problem, replace the drain pump. The motor could possible be failing. The part number on the Sears website is 154580301 and costs about $40. Repairclinic.com has the same part listed as item #1257094 for $37.50 if you wish to do some comparable pricing.
I hope this helps you. If you need further assistance, please post back and let me know.
PS Even the quietest of all dishwashers will make some noise. However, if it has gotten to the point where you can hear it in the next room, you probably need to inspect to find the source of the problem. This is not true with all dishwasher manufacturers, but in many cases, the only difference between your "Quiet-Pack" line and regular low-end models is added insulation behind the door and lower panel to help quieten noise.