I have an Electrolux-made dryer but it does not have the ball-and-hitch bearing design, AFAIK. It has three rubber rollers that are bolted to the frame which the drum rides on. I have seen the plastic duct they are talking about, though. When I took my dryer apart to clean it last autumn, I noticed the large grey plastic blower housing/exhaust duct. Luckily, mine had very little lint buildup.
I also saw the heating element is entirely different than the older rear-coil design. It has what looks like a gas burner box under the drum, which contains several electric heating coils.