In the 1980s, Mercedes-Benz was high on the fumes of its collective neurosis—it got so bad that not even the smallest detail could escape intensive over-engineering of the highest order.
I actually owned a vintage Mercedes, and I got rid of it because I learned that a minor vibration at about 60 Mph could only be fixed by removing the entire exhaust system and replacing tiny flexible discs and braces found throughout the driveshaft. You also had to replace a $1,500 (out of production) gas strut that kept the car from going bow-legged from the swing axel.
And my car was designed in the SIXTIES.
By the mid-80s, the engineers over at Benz had gotten so bored with making the most over-engineered cars on the planet—they decided to spend millions researching and developing a solution to a problem that didn’t exist: they reinvented the windshield wiper.
Apparently, the windshield wipers that every Mercedes-Benz model had been using for a few decades simply weren’t good enough for the new E-Class sedan.
A Wiper Nobody Asked For
The engi-nerds were convinced conventional wipers didn’t cover enough of the windshield and didn’t have enough small hard to fix moving parts in them. The result was the infamous Monoblade wiper—a needlessly complex and heinously expensive to produce a mechanism that was in use for well over a decade.
Mercedes used a central arm hub on the W124 and a set of small concentric gears along with an articulating arm inside the wiper arm itself to achieve and almost perfectly square wipe across the windshield.
This yielded an impressive 86% coverage of the windshield, up a whole 6% from what is required by law via the NHTSA. That’s right—a 6% increase in coverage. While the new Wunder Wiper was technologically innovative, it did have several serious problems.
The single wiper couldn’t clear the screen as fast as a dual wiper system: this meant the motor had to be more powerful, and therefore more expensive than a conventional motor. It also meant that all the parts in the system were subjected to more strenuous wear.
The Monoblade Wiper Broke. A Lot.
When they failed, which happened somewhat frequently, you were left without any wipers at all. This actually happened to my aunt in her W124 on multiple occasions, and when the warranty on her beloved Benz lapsed, the dealer charged about a grand to replace the system.
This was after she was left stranded on the side of the road in a flash flood because her (singular) wiper stopped working. If that wasn’t bad enough, internal Mercedes research also found that the wiper could have a “hypnotizing effect” on drivers…fucking wonderful.
Back to the Basics
Mercedes eventually scrapped the Monoblade and returned to a conventional system sometime in the mid-2000s. Frankly, I take comfort in this—mainly because it means that Germans are willing to admit it when they’ve made a mistake.
Somehow that helps me sleep soundly at night. I have no clue why, though.
*Technical Footnote: Mercedes never actually referred to this design as a "mono wiper" or "mono-blade." The official terminology is "eccentric sweep." So if you go looking for this on the internet, that's the term to use. There are many videos on YouTube—and they are actually kind of hypnotizing to watch…Great to fall asleep to.