Fumoto Oil Pan Sludge?

Was planning on installing one of these Fumotos on my Tacoma and saw this: http://www.powerstroke.org/forum/6-...warning-oil-drain-valves-ez-drain-fumoto.html

Essentially what is initially talked about is how old oil accumulates in the bottom of the pan because the threads of the Fumoto stick out above the bottom of the pan itself, basically allowing old oil to puddle, accumulate and eventually sludge up.

Anyone have any experience on this?

 

It's a non issue and using a power stroke diesel for comparison is probably not valid. Is there a little oil left in the crank case after a drain, probably. Sludge is more a function of infrequent oil changes and oil temps than residual oil left in the engine after an oil change. Additionally, beside the crank case, there is residual oil in crank journals, oil pump, oil galleries, etc. An oil change never drains all of the oil, it is just diluted with the fresh oil.