A hifi head guy showed me an old SAAB part, unless he's misguided they used pneumatic actuated user panels long ago. Felt insanely overengineered .. but pretty sexy at the same time.

For what its worth, up until 1970-71, vacuum operated things in cars (locks and and I think windows) were not uncommon, even beyond that, up until basically the start of the current era (2010), vacuum operated air conditioning systems (to change the flow of air) were the norm too (I suspect they still are on ICE cars). In addition, most cars with concealed headlights used vacuum motors to open and close them.

Furthermore, windshield wipers were not infrequently powered by the power steering system, rather than electrically driven. High torque electric motors in a small enough package and affordable enough didn't exist until the late 60's.

Not a mass-market product, but another fantastic anomaly in automotive engineering is the hydraulic system used to power the accessory systems in the Mercedes 600; the classic chariot of late-20th century despots and celebs.

It ran on mineral oil at a nominal pressure of IIRC 3200 psi. Could cleanly slice a finger off if poorly maintained & it sprung a leak in an inopportune corner of the system. All this to ensure that the auto's accessories operated with all the smoothness and silence that befitted a head of state.

Yeah ... and some (like my 99) had alterations made at the U.S. point-of-entry. The added A/C system was so cold it would freeze your body parts. Since the air-ducts were routed through the glove box (who doesn't want heated gloves in the winter), this also resulted in having ice-cold Cokes in the summer :)

I'm pretty sure my 1982 SAAB 900 Turbo (bought used in 1988 with about 94k miles on it from original owner) had pneumatic actuation for the dials...but it's long gone and i can't check now.

> pneumatic actuated user panels

What does that mean?

the buttons would control other parts of the car through air pressure, it was bidirectional too IIRC

not sure, he only had half of a device in his shop

The Saab Sonnets are beautiful little things, especially in orange.

The one I'm working on was originally somewhere between lime and avocado green and was wrecked with about 70K miles on it in 1975. It's been in a garage ever since. The downside of a fiberglass body is that it shatters in ways a metal body wouldn't. The upside is that repairs can be as smooth and as strong as the original.

how worried should I be about Saab 900 ('78-'94) and its manual transmission reliability? I adore this car (and its lovely seats) so much I'm tempted to buy one but I hear its manual tranny is fragile.

My 900 had the automatic transmission which turned the car into a real dog. It had the same engine as my 99 but was a heavier car. My Father-in-Law had a special edition 900 with the standard transmission and it was an amazing car. It had very few mechanical problems but was unfortunately claimed by rust caused by our central PA winters.