Timers
I can't find it now (of course), but there was a first rate posting on rewiring the motors used on a lot of these. A lubricant which turns to solid cement and motor windings with a near 100% failure rate.
When it's working, the timer is not at all stiff to turn, by the by. When we got ours, I doubt I could have budged it with a 2 meter cheater bar.
Our dryer's timer works, thanks to Greg. But, oh, my, I think I put more time into the timer than the entire rest of the dryer together.