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Windshield wipers

Why do most car manufacturers have the windshield wipers go from right to left instead of left to right, which cleans the driver’s side better?

For the same reason that there are 8 hotdog buns to the pack and most hotdogs come in 10 packs.

It seems to me that wipers going from right to left clear the driver’s side better. I had a 1948 Dodge and the wipers went from left to right on the driver’s side. The extreme left side of the driver’s side wasn’t cleared. The Chevrolet Uplander I owned had the driver’s side wiper going from right to left and the passenger’s side wiper going from left to right. The wiipers overlapped to clear the center of the windshield.
It seems to me that wipers gave better visibility when they came down from the top of the windshield rather than coming up from the bottom, but you have to go back to the 1930s to get that arrangement.

If you are in the US (or other countries where the driver sits on the left side of the car), it is preferable to have the wipers go from right to left, instead of the other way around.

When your wiper moves to its furthest-left position, it wipes very close to, and parallel to, the left roof pillar, leaving probably no more than 1/2 inch to 1 inch of unwiped area on the left.
Conversely, if the wipers operated as you wish, there would be an arc of unwiped windshield area on the left that would obscure much of your vision.

If you can’t visualize what I am describing, sit in the front passenger seat, and see how much less wiped area exists in front of the passenger.

Heck, I was intrigued by the single wiper on a Yaris and how much windshield it covered; about the only thing that did intrigued me about the car.

My 59 Pontiac went R to L on the drivers side and L to R on the passenger side. Full sweep R to L was a decided improvement from that.

Somewhere back in the '70s the DOT made it mandatory for a certain percentage of the windshield to be wiped on each swipe. MG did it with THREE small wiper blades. Somewhere in the '80s Mercedes started complying with only one blade. That one blade moves across the glass pretty darn quick. It’s 24" long on one of mine.

Which cleans the driver’s side better is entirely a function of the windshield and wiper designs. Some European manufacturers (I think Porsche is one) atill use one wiper on some of their cars.

The single wiper Yaris and the 1980s Mercedes had nothing on some of the cars of the 1930s and even some trucks through the late 1940s. In many low end vehicles, there was only one wiper on the driver’s side. A passenger side wiper was an option. I know that through 1949, a passenger side wiper was an option on the Ford F-1 pickup truck. Of course, the single wiper on these vehicles didn’t clear much of the windshield.

Yup @Triedaq, and on my Model A Ford truck the I turned a little crank inside the cab to move the wiper from side to side. I think the blade was about 8" long, but that’s an old memory from when I was a kid, and the truck was an antique even then.