I removed the drum and the left roller is definitely rolling in a far less smooth way than the right roller, though they both look fine. Here's what I need to know:
1) What is the thing holding the roller on that looks like a little 2-D blast helmet for the bolt (photo) and how do I get it off?
2) Is there anything tricky like loose ball bearings lurking behind the roller ready to spring/fall/self-destruct once I get the thing in #1 off? Or any other weird things to expect after I get the roller off that will send me crawling back to the forum?
3) If I do have to replace the roller, should I replace them both for symmetry's sake, or just the crummy one?
Speak slowly and use small words, O Samurai, for I am venturing into my first major appliance repair.