Right. I restore antique Teletype machines from the 1930s and 1940s as a hobby. Those are totally maintainable. Everything is attached with screws and locknuts, and you can remove and replace any part. There's a 200 page manual of adjustments. They require annual oiling with over 500 oiling points. Most take one drop of oil, but there are several oil fill points. In heavy use, there's an annual cleaning, which involves partial disassembly and a soak in a cleaning bath in a repair shop. I've restored five of these machines to full operation. Some are almost a century old.

(Plug: some of those machines will be at the Clockwork Alchemy Steampunk Convention, at the Doubletree Hotel in San Jose CA, tomorrow through Sunday.)

Imagine trying to sell a printer today that required regular oiling. That would not be acceptable, even if it increased the life of the printer by a factor of 5.

Teletype Corporation recognized this with the Teletype Model 33, the yellow plastic thing that powered 1970s minicomputers. Those were rated for one year of continuous operation un-oiled, three years if regularly oiled. Few people oiled them. They wore out much faster than the older heavy-duty machines. Today, it's easier to restore a Model 15 Teletype from 1930 than a Model 33 from 1970. The 33 will have worn out parts, some plastic. The Model 15 won't; it's all hardened steel and cast iron.

There are heavy trucks built that way, but cars? No.