My dishwasher started leaking one night - luckily I was nearby when it began. Upon researching I learned that it was caused by a failed grommet that's installed with its garter spring facing towards the water-filled tub, which causes premature failure after 2-3 years. Of course Whirlpool stopped selling the grommet as a replacement part, instead requiring people buy an entire $150 sump assembly.
So I bought a few $5 grommets off a grommets-r-us site and have scheduled a triennial dishwasher disassembly song and dance. Threw a simple leak detector under the washer just in case. At least now I'm pretty knowledgable of the secret life of the dishwasher.
The drum is moved by a belt so thin I thought it was a piece of string to tie it in place.
The tensioner on said belt was literally nothing more than a bent coat hanger with a little plastic pulley. This part of the design was important because the "emergency stop" in the even of the belt breaking was that the coat hanger would go flying off into the machine and stop pressing against a little micro-switch glued to the side of the motor mount.