We have a Maytag Centennial dryer (Model # MGDC700VW0) that has had its lint filter neglected too many times in-between runs. When the lint filter is over-full, pulling it out actually lets lint spill into the lint duct assembly (bulkhead part #45 at the bottom of this diagram) and accumulate there. It's only year old, but at this point, the dryer is taking too long to dry, and I'm attacking this as the first culprit. (I'll also be cleaning out the short vent duct, too)
The old dryer we had could have the top pop up, revealing a couple set screws that held on the front. Not this unit :-( ...I've spent about 2 hours (and one blood-blister) trying to get into it.
Does anyone have any ideas besides an acetylene torch? :-)