Best of 2020: Automotive History: The Mystery of GM’s Two Wiper Systems (The Answer Was Pretty Obvious) – And More Wiper History

(Dave Skinner contributed key technical info to this post)   At Dave Skinner’s recent 1964 Olds Jetstar 88 post, eagle-eye Jim Cavanaugh once again raised the question that had been bugging him for years: why were there two different wiper systems used on these B-Body Olds? The low-trim Jetstar 88 (top) has what GM termed as the tandem system, where the two wipers work essentially parallel to each other. The slightly more expensive Olds Super 88 (below) as an overlap system, where the wipers are mounted far apart and overlap in the middle.

I had never noticed that disparity, and became intrigued, and started doing some research via Google searches and at oldcarbrochures.com. Meanwhile, Dave Skinner went down to LA Central Library to dig up the technical data on these systems. So we’ve combined forces, working both in tandem and with a bit of overlap to wipe away any lingering confusion and mystery.

But first, let’s do a bit of wiper history.

Early wipers were often mounted above the windshield and commonly manually-powered. By the mid-late ’30s, most seem to have settled into the format seen until the end of the split windshield, which of course dictated that they not overlap, as on this ’49 Olds.

Even with the advent of one-piece windshields, the wipers still stayed the same.

And that’s how things stayed at GM through 1960, with center-meet wipers (no overlap).

But for 1961, GM came out with no less than two new wiper systems. On higher trim Pontiacs (Ventura and higher) and Olds (Super 88 and higher), all Buicks and Cadillacs, the center-meet wipers now had a decided overlap in the middle. This undoubtedly reduced the amount of unwiped area on the windshield.

Meanwhile, the lower trim Pontiacs (Catalina) and Olds (Dynamic 88/Jetstar 88) and all full-size Chevrolets got a totally new tandem wiper system. Maybe it’s already not such a big mystery as to why.

 

Dave found these two descriptions of the wiper systems in options brochures. The overlap system came standard as a two speed system, and the washers (with an electric pump) were optional.

The tandem/parallel system came standard with a one-speed motor, and a two speed motor with washer pump was optional.

Here’s a more detailed description of the two systems and what was optional:

  • The base models offered single speed wipers with tandem action.
  • The dealer could add a washer pump to the single speed wiper system.
  • The base model cars could be upgraded to two speed wipers, but kept the tandem wiper action.
  • The Super 88, Starfire, and 98 offered two speed overlap wipers including a washer pump.

Here’s some detailed images Dave found in the 1964 Olds Service Manual that show the guts of these systems. Here’s the tandem system.

And here’s the overlap system. And the mystery is of course solved: the tandem system used significantly fewer parts in its mechanism, not needing the center pivot (located at the same spot where the passenger side tandem wiper base mounted) and second mechanism arm from there to the outside wiper and its mounting. These parts undoubtedly weren’t exactly expensive, but over volumes of millions of cars, every penny adds up.

Where did the tandem wiper system originate? At GM, with the 1960 Corvair, where every possible penny saved was critical, and the tandem system worked well enough.

And the 1960 Ford Falcon had the same kind of tandem wipers too.

But the 1960 Valiant still had the center-meet, non-overlap wipers. And that was pretty much the case for all American cars at the time.

Rambler, like Studebaker and the all the rest, also used center-meet wipers, but it seems that starting in 1960, there was a bit of overlap to them, at least in some of the pictures I could find. Maybe folks just had the wrong sized blades on them?

But the 1961 Ambassador, with its larger windshield, clearly had some overlap to its wipers.

Chrysler stuck with the center-meet (non overlap) wipers through 1964 on its big cars, 1965 on the B-Bodies, and 1963 on the A-Bodies.

Then switched to tandem wipers on the subsequent years: 1965 C-Body, 1966 B-Body and 1963 A-Body.

Ford stuck with the traditional center-meet (non-overlap) wipers through 1962 on the big cars.

 

Switching to tandems in 1963. The 1962 Fairlane had tandems like its platform-donor Falcon.

The 1961 Thunderbird had overlap wipers quite similar to the GM ones. It kept them through 1966, and switched to tandems in 1967 when it went to the new BOF platform.

Meanwhile, the 1961 Continental played to a different drummer: it had tandem/parallel wipers, but mounted the opposite way of just about every other tandem system.

Why? Looking at this picture, the new Continental’s pronounced tumblehome created a windshield with a decided slant, looking at it from the front. That actually suited the arc of that wiper quite well, and it wiped the lower corner of the driver’s side much better than either a center/overlap or typical tandem system. Lincoln kept this unique system through the unibody era, ending in 1969. Then came conventional tandem wipers.

So what about GM after 1964? A good question, as there’s even more curious goings-on there. Chevrolets kept the tandem system.

A Google search for 1965 Pontiac Catalinas confirms that although some Catalinas, like this 2+2 did still use the tandem wipers, a majority of images show the overlap wipers. Was the tandem system eliminated mid-year, or just a factor of the production mix? Brochure shots show only overlap wipers, but clearly there were some built with tandems too. But I couldn’t find a single 1966 Catalina with tandems. And that applies to all the 1965 Olds B-Bodies too; no more tandems. They were now relegated to Chevy, but not for long.

In 1967, Pontiac pioneered the hidden wiper system, and as can be seen here on this Bonneville, it’s still an overlap system, but there’s now a second arm on each wiper, to create the articulation necessary to lower the blades below the lip of the hood. Pontiac kept this system through 1969.

But in 1970, Pontiac reverted to the tandem system.

I couldn’t find a suitable shot for a 1968 Olds 88, but the two fuzzy ones I found showed that they used the same tandem wipers as this 1970 88. Only the driver’s side is articulated.

It looks essentially identical to the ones under this 1968 Chevrolet hood. And Buick used it too. So when Buick and Oldsmobile B and C bodies moved to hidden wipers in 1968, they all used a tandem system with articulation on the driver’s side, except Pontiac.

Cadillac also stuck with the overlap wipers after moving to the hidden versions in 1968. Like the Pontiacs, they are articulated on both sides, apparently necessary to make them hidden.

But not for long. By 1969, Cadillac joined the rest of the GM tandem brigade.

And with the new 1971 B and C Bodies, everyone now had the same tandem system, as they would going forward.

So hopefully we’ve wiped away the mystery of GM’s two wiper systems, and cleared up some other related wiper history.