From NDLR To PRNDL – How One Inventor’s Grudge Against GM Helped To Standardize Transmission Shift Patterns

 

Have you ever wondered why modern automatic transmissions all have shift patterns beginning “PRND”? It wasn’t always so — if you’ve driven older cars, you may have noticed that they often placed reverse at the other end of the shift quadrant, next to Low. Why that changed is a complicated story involving the early GM Hydra-Matic transmission and an inventor named Oscar Banker, who nursed a decades-long grudge against General Motors.

Today, automatic transmission shift patterns on most U.S.-market cars, trucks, and buses are governed by Federal Motor Vehicle Safety Standard No. 102 (49 CFR § 571.102), which requires (among other things):

• A neutral position shall be located between forward drive and reverse drive positions.
• If a steering-column-mounted transmission shift lever is used, movement from neutral position to forward drive position shall be clockwise.
• If the transmission shift lever sequence includes a park position, it shall be located at the end, adjacent to the reverse drive position.

The original version of this regulation was established back in February 1967 as the part of the first batch of federal safety standards. It was adapted from an earlier General Services Administration (GSA) regulation, Federal Standard No. 515/11, which applied to federal fleet cars beginning July 1, 1966.

By 1966, the domestic auto industry had already grudgingly standardized the PRNDL shift pattern, but it had been a slow process. Until the early 1960s, many U.S. automatic transmissions, beginning with the first Hydra-Matic Drive of 1940, used shift patterns that placed Reverse at the opposite end of the quadrant, adjacent to Low.

 

Why? Transmission designers of the the ’40s and ’50s were preoccupied with ensuring that automatic transmissions still provided for a number of functions that may now seem rather quaint, including push-starting of stalled cars and the ability to “rock” a car’s drive wheels free of mud or snow by shifting rapidly between forward and reverse. To allow push-starting, the designers of Hydra-Matic included a separate rear oil pump; to facilitate rocking, they placed Reverse next to Low. Early Hydra-Matic transmissions had no separate park position, so their shift pattern was NDLR.

 

Many other early automatics also adopted these functions, and the NDLR or PNDLR shift pattern. Prominent examples included Buick Dynaflow (1948), Packard Ultramatic (1949), Chevrolet Powerglide (1950), and Studebaker Automatic Drive (aka Borg-Warner DG, also 1950).

 

Since GM’s Detroit Transmission Division also sold Hydra-Matic to various non-GM customers, including Lincoln, Nash, Kaiser-Frazer, and Hudson, this shift pattern became by far the most common on automatic transmissions of the early ’50s.

 

The first new automatic transmissions to depart from that pattern were the 1951 Ford-O-Matic and Merc-O-Matic, also developed with Borg-Warner, which adopted a PRNDL pattern “after considerable study.” They were followed in mid-1953 by Chrysler, which adopted an RNDL shift pattern (with no Park position) for the two-speed PowerFlite. However, the ability to rock the car between forward and reverse was considered so important that both companies took pains to explain that their arrangement was still adequate for that purpose, and most manufacturers that used the NDLR/PNDLR pattern continued to do so.

 

After a while, there were various different shift patterns for different automatic transmissions, which placed Reverse in different parts of the pattern and required different selector motions (e.g., pulling up or back) to access certain ranges. This was potentially confusing for drivers, not helped by the fact that shift quadrants weren’t always well-lighted, and their selectors didn’t always clearly (or accurately) indicate which range was selected.

 

So far as I know, the first prominent Detroit engineers to publicly suggest that placing Reverse next to Low was categorically less safe (rather than just potentially confusing) were Chrysler’s William R. Rodger and A.J. Syrovy, during their presentation on the new PowerFlite transmission at the January 1954 SAE meeting in Detroit. Rodger and Syrovy argued that placing Reverse next to Neutral was safer because a “shift from neutral to reverse does not require going through a forward gear, with the danger of the car leaping forward when idling fast.” (When Ford had introduced Ford-O-Matic and Merc-O-Matic two years earlier, they had merely suggested that going from Reverse to Neutral to Drive was more convenient; at the time, Ford was still buying Hydra-Matic transmissions for Lincoln, so they don’t appear to have been too concerned about any safety implications of its NDLR shift pattern.)

 

Rodger and Syrovy called for standardization of automatic transmission shift patterns. While that was a reasonable request, the problem was that there wasn’t any clear consensus on what the standard should be, so most manufacturers just continued doing what they were already doing, arguing that a change would confuse their existing customers.

 

The SAE Hydrodynamic Drive and Transmission Committee briefly considered pushing for standardization, but dropped the idea when the industry became fascinated with pushbutton controls in 1955, arguing that “with the introduction of push-button shifting devices, the shift selector may eventually be replaced.”

 

The result was that by the latter half of the ’50s, getting into an unfamiliar car required looking carefully for Reverse. Even brand-loyal customers might be confounded — for example, Chevrolet and Buick used different shift patterns for their triple-turbine torque converter automatics, Chevrolet Turboglide and Buick Flight Pitch Dynaflow, than for the more common Powerglide and Variable Pitch Dynaflow transmissions. Chevrolet addressed this for 1958 by switching Powerglide to a PRNDL pattern, but Buick didn’t bother.

 

By that time, the contention that the GM NDLR/PNDLR shift pattern was unsafe had been taken up by a different and much louder voice: a Detroit outsider named Oscar Banker.

The Agonies of Oscar Banker

Armenian immigrant Oscar H. Banker, born Asadoor Sarafian, was a mostly self-taught machinist, engineer, and inventor who received an astounding number of patents during the course of his life (more than 150), in fields ranging from band saw sharpening to medical tools. Sadly, as becomes immediately clear if you read his 1982 memoir, Dreams and Wars of an American Inventor, published three years after his death, Banker was also a bitter, cantankerous, self-promoting fabulist with a capacity for grudges that would have shamed even the notoriously unforgiving Frank Sinatra.

 

In the automotive realm, Banker is best known for his often-repeated, demonstrably false claim that he developed the first practical automatic transmission and created “the first car with no clutch pedal nor gearshift [sic].” It is true that beginning around 1926, Banker designed an automatic transmission, later called Mono-Drive (or Monodrive), variations of which were used in some railcars and several hundred city buses in the mid-to-late 1930s. However, Mono-Drive was definitely not the first automatic transmission in any sense (the Sturtevant brothers of Boston patented the first iteration of theirs when Banker was still a young boy), and its commercial and technological impact was minimal. Banker’s was just one of many early attempts at self-shifting transmissions, now mostly forgotten.

 

This inconvenient fact didn’t stop Banker from continuing to insist, to the end of his life and posthumously afterwards, that he was the “father of automatic transmission” and suggesting that his transmission was the wellspring from which all later practical automatic transmissions came. In particular, he claimed that GM’s Hydra-Matic Drive was developed to “duplicate the principles of my transmission, but with adequate differences, so they wouldn’t be forced to use my unit.” There was no more truth to that than Banker’s assertion that he was the first to develop a car with no clutch pedal, but Banker apparently believed it, and he was still angry about it decades later.

 

How he came to think that is convoluted: According to Banker’s account (which has to be taken with a grain of salt), he first demonstrated his Mono-Drive prototype to auto industry officials in 1930. Despite the considerable derision his prototype received from some GM engineers — including Earl A. Thompson, then a Cadillac engineer — Banker claimed that General Motors had been prepared to license the design. Negotiations collapsed because Banker’s then-business partner demanded too much money, but in 1934, Banker and his backers managed to interest the Omnibus Corporation, and through them, Yellow Coach & Truck Co., a GM subsidiary, which licensed Mono-Drive for use in city buses, despite Banker and his partners once again demanding what Yellow Coach considered an unreasonable amount of money. Yellow Coach built approximately 600 buses with the Mono-Drive transmission through late 1938.

 

In December 1935, Yellow Coach development engineer Howard Broadus told Banker that Earl Thompson was now leading a GM Engineering Staff project to develop an automatic transmission (which eventually yielded the semiautomatic Automatic Safety Transmission and the 1940 Hydra-Matic). Broadus allegedly told Banker that the Thompson project was intended as an in-house substitute for Banker’s design. If Broadus actually said that, he was wrong: The Thompson automatic transmission project was intended primarily for passenger cars, not buses, and while Yellow Coach did abandon Banker’s Mono-Drive in 1938 in favor of another transmission, it was a torque converter unit made by Spicer, which was not in any way related to the work of Thompson’s group.

 

Nonetheless, Banker became convinced that every conflict he had with Yellow Coach was really because GM was double-crossing him in order to steal his ideas. He saw the 1936 transfer of Yellow Coach engineer Oliver K. Kelley to Thompson’s group as further evidence of GM’s treachery and “deception,” and later claimed that the 1940 Hydra-Matic transmission was “openly defying our patents.” There was nothing in that — Hydra-Matic was so different from Mono-Drive in operation and principles that it’s highly unlikely that Banker and his partners could have proved infringement even if they had tried, which they didn’t. Judging by Banker’s account, he would probably have regarded ANY GM automatic transmission developed during that time as an attempt to sabotage and rob him, regardless of its actual design.

 

If you read Banker’s memoir, this pattern is repeated again and again: In Banker’s anecdotes, people he admires always lavish him with praise for his brilliance; people he dislikes or regards as rivals always lash out childishly in their pride and envy; and deals that should have made him a wealthy industrial tycoon always fell through or fell apart due to someone else’s petty jealousy and nefarious sabotage. Those slights, real or imagined, seem to have occupied a much bigger place in Banker’s mind than the deals that didn’t fall apart. For instance, so far as I’m aware, Borg-Warner, which licensed Banker’s Mono-Drive patents in 1936 for non-coach applications, never did anything with the design except sit on it, but that point gets far less ink in Banker’s memoir than his feud with GM.

The “Booby Trap” Pattern

For all his hostility towards Hydra-Matic, Banker doesn’t seem to have been terribly familiar with the GM transmission, and he didn’t follow its subsequent developments very closely. However, he eventually became fixated on its NDLR shift pattern, which he came to insist was a deadly “booby trap” because a driver might inadvertently select a forward gear when trying to shift into reverse.

 

A reality check is in order here: I don’t doubt that there were some accidents resulting from the confusing array of different automatic transmission shift patterns, and some of them were probably caused by drivers getting Drive or Low when they wanted Reverse (which can happen even with standardized shift patterns). However, Banker wasn’t content to just say that — he asserted over and over again that the Hydra-Matic shift pattern had caused “countless accidents” and that “thousands of persons lost their lives through this defective design.”

 

This was an extraordinarily bold claim, and the only evidence Banker ever offered for it was a handful of newspaper clippings about individual car accidents and his very dubious contention that, based on “the Gallup principle of sampling,” each incident that made the news must have represented dozens if not hundreds more unreported disasters. Without belaboring the point, that’s not how sampling works, and the suggestion that automatic shift patterns were responsible for a vast death toll that no one other than Oscar Banker had ever bothered to notice was preposterous.

 

Furthermore, Banker laid most of the blame for this alleged death toll specifically on Hydra-Matic, which is interesting given how widespread the NDLR/PNDLR shift pattern was by the mid-’50s. To the extent Banker acknowledged that other automakers used the same shift pattern, he implied that they had blindly followed GM’s lead, even though they had no good reason to. (Banker had a distorted idea of why Hydra-Matic adopted the NDLR shift pattern — because the explanation is technically involved, I’m not going to get into it here except to say that Banker’s contention that the early Hydra-Matic used the NDLR shift pattern because the transmission otherwise wouldn’t go into reverse was off-base, and it exposed his limited understanding of how Hydra-Matic actually worked.)

 

Notably, Banker’s criticisms seldom seemed to land on Borg-Warner, although Borg-Warner also used the PNDLR pattern extensively in the ’50s and early ’60s. But, then, Borg-Warner was still paying Banker license fees on his Mono-Drive patents through 1957, while the money he had received from Yellow Coach in the ’30s had long since been spent. In Banker’s mind, Borg-Warner had properly respected his genius and GM had not, which made Hydra-Matic morally suspect on its face.

Banker’s “Little War” Against GM

At the SAE meeting in Detroit in January 1956, Banker attended a presentation by Kenneth Gage and P.J. Rhoads of Detroit Transmission Division about the new second-generation Controlled Coupling Hydra-Matic. During the Q&A segment, Banker stood up and proceeded to harangue Gage and Rhoads about why they had retained the familiar Hydra-Matic “booby trap” shift pattern for the new transmission.

 

Like nearly all of Banker’s statements on this subject, his question was prefaced by a lengthy diatribe about how he had developed the first practical automatic transmission. I don’t think this went over well at all: He was ranting at a room full of powertrain engineers, some of them veterans of long standing, about how he was really the originator of their work — a boast he then punctuated with unsubstantiated claims about the many fatalities allegedly caused by the NDLR/PNDLR shift pattern (which many of the other attendees were also using).

 

Gage and Rhoads replied that the new Hydra-Matic retained the existing shift pattern (although it now had a separate Park position, located to the left of Neutral) “to enable the vehicle to be rocked between low and reverse.” They added that with more than 7 million Hydra-Matic cars already on the road, Detroit Transmission Division felt it made little sense to change the now-familiar Hydra-Matic shift pattern.

 

Banker repeated this performance at other presentations at the 1957 and 1958 SAE Detroit meetings, delivering a similar combination of boasts, accusations, and hyperbole. When Chevrolet adopted the PRNDL shift pattern for the 1958 Powerglide transmission, Banker took credit for the change, insisting that it was his impassioned speeches that had led Chevrolet engineers to finally do the right thing, rather than that they had wanted to make the Powerglide pattern more consistent with Turboglide, the stated rationale.

 

This “little war,” as Banker characterized it, quickly made Banker an unpopular figure in Detroit. He lamented that people began to treat him like a leper, and his calls were no longer returned. At least two of Banker’s friends in the industry tried gently to convince him to give it a rest, but Banker took this to mean that many people secretly agreed with him and were just afraid to admit it, so he dug in his heels.

 

When Detroit Transmission chief engineer Walter B. Herndon made his presentation about the third-generation Hydra-Matic at the SAE Detroit meeting in January 1961, Banker was there again, delivering his now-familiar diatribe and demanding to know why the latest Hydra-Matic still had the same shift pattern.

 

Herndon gave him the same answers as always: The shift pattern facilitated rocking; it was familiar to Hydra-Matic customers; and after building over 10 million Hydra-Matic cars, Detroit Transmission had no intention of changing it.

 

Banker took this very badly, perhaps in part because it came from Walter Herndon — as Banker probably knew, Herndon had been part of Thompson’s transmission group back in the ’30s, and had been one of the architects of the original Hydra-Matic. In May 1961, Banker wrote an impassioned letter to GM president John F. Gordon, again claiming that he was “known among automotive engineers as the ‘father’ of automatic transmissions,” and ranting about the “very stubborn” GM engineers who refused to change the “unsafe” shift pattern out of what Banker insisted was nothing more than foolish pride. A week later Gordon replied, with bland patience:

The matter of the transmission shift sequence has been discussed on several occasions and we can assure you that the proponents of the two sequences currently used on our cars are equally vehement in their support of what they are now using. Both groups bring forth equally valid reasons for continuing their present practice and I use the term “equally valid” after discounting for such influences as “fatherly interest,” “engineering necessity,” etc.

After each review of the situation, our conclusion has been and very probably will continue to be that we will make no change in our present practice.

Oscar Banker, New York, and Ralph Nader

Outraged by Gordon’s response, Banker began a letter-writing campaign, reaching out to TV news producers and the editors of Reader’s Digest, the Saturday Evening Post, and various newspapers in hopes of drumming up a public scandal about the issue. The replies were dismissive, which he later insisted was because everyone was too terrified of offending GM. (He may have been at least half-right; I don’t imagine many magazine or newspaper editors were keen to risk clashing with General Motors over the rantings of an obvious crank.)

 

However, Banker made enough noise that he was invited to come to Albany, New York, to testify before the New York Joint Legislative Committee on Motor Vehicles & Traffic Safety. (He later asserted, with customary modesty, “I was invited to express my views on shift pattern dangers out of respect to me as father of the automatic transmission.”) Afterwards, he made 300 copies of his testimony and mailed them to dozens of auto industry executives.

 

The committee then asked Banker to create a questionnaire to be distributed to New York City and state police to help identify accidents related to automatic transmission shift patterns. This questionnaire became perhaps the single most dishonest tactic of Banker’s one-man war on GM: He advised New York law enforcement officials that “if anyone stated that his accelerator froze while exiting a parking lot or trying to park, it simply was not true” and was in fact another incident of “the endlessly repeated pattern of the [transmission shift pattern] booby trap deadly accident.” It was incredibly specious, and it made any actual data gathered using his questionnaire of very little value. Nonetheless, the New York committee seemed to accept Banker’s advice and purported expertise at face value; I can only assume that their relationship with the auto industry was so adversarial that they weren’t deterred by his negative reputation in Detroit.

 

In 1963, Banker also came to the attention of a young attorney named Ralph Nader, who was already becoming a public figure in the campaign for auto safety. Although Banker and Nader apparently never met in person, Nader wrote to him in early 1963, asking for more information about Banker’s complaints about GM transmissions, which Banker enthusiastically supplied. They corresponded again in 1965, and Nader included a condensation of Banker’s customary diatribe in his book Unsafe at Any Speed.

 

Ironically, although Unsafe at Any Speed greatly increased Banker’s visibility, Banker quickly regretted being associated with Nader. When he learned of Nader’s condemnation of the early Chevrolet Corvair, Banker became outraged, insisting that Nader’s charges were “a hoax” (they weren’t) and later lamenting (inaccurately), “I am known to many engineers and industrialists yet today as ‘the man who made Ralph Nader.’ I can never live down that charge, true or not. I will take it to my grave.”

GM Switches Gears — and Shift Patterns

In the late summer of 1963, Detroit Transmission Division (which was renamed Hydra-Matic Division on October 1) launched the new Turbo Hydra-Matic transmission, which would shortly replace the older second- and third-generation Hydra-Matic transmissions. Turbo Hydra-Matic finally abandoned the traditional Hydra-Matic shift pattern for a PRNDL/PRNDSL pattern. The older Hydra-Matic transmissions, which retained the PNDLR and PNDSLR patterns, remained in use through 1964, but they were on their way out.

 

Inevitably, Banker insisted that this change was due to his efforts. (His memoir describes an alleged encounter with Chevrolet chief engineer Harry Barr at the 1963 SAE convention in Detroit in which Barr supposedly told him that Banker’s testimony to the New York traffic safety committee had made all the difference, but that anecdote was so improbable, and so factually and chronologically dubious, that I seriously doubt its veracity.) In a letter to Banker on December 28, 1963, Henry H. Wakeland, the automotive consultant for the New York committee, also credited Banker for GM having “apparently abandoned the Hydra-matic shift pattern.”

 

I suspect the bigger concern for Detroit Transmission Division was that they were now in real danger of becoming the odd one out. By mid-1963, virtually all the low-priced makes had adopted PRND shift patterns, as had Lincoln; Buick would drop its PNDLR Turbine Drive and Dual Path Turbine Drive transmissions at the end of the 1963 model year. Detroit Transmission was probably still concerned about the collapse of their previous non-GM Hydra-Matic sales — the second-generation Hydra-Matic had proved too expensive, and the lighter, cheaper third-generation transmission hadn’t made any headway against Borg-Warner — and while returning customers might be familiar with the existing shift pattern, there was some risk of alienating new ones more accustomed to the PRNDL shift patterns used by other manufacturers.

 

It was a similar story at Chrysler, which also dropped its signature pushbutton transmission controls after 1964. As Car Life explained (January 1965), “Chrysler market analysts discovered that prospective buyers were shying away from the buttons, apparently due to a combination of their unfamiliarity and the difficulty of accepting the button as a power symbol.”

 

Contrary to popular belief, neither change had anything to do with the GSA federal fleet car regulations. The law that authorized the GSA to establish such rules wasn’t signed until August 30, 1964, by which time production of pushbutton Chrysler TorqueFlite and older GM Hydra-Matic transmissions had already wound down. The GSA didn’t issue the first draft of its regulations until January 26, 1965; they weren’t finalized until June 30, 1965, and they didn’t take effect until a year after that.

 

However, I think the GSA regulations were likely influenced by Banker’s testimony to the New York traffic safety committee. The requirements for automatic transmissions under Federal Standard No. 515/11 read like this:

• 53. Standard characteristics. The propressive [sic] sequence of the manual control mechanism shall be reverse drive position, neutral position, and forward drive position. Drive positions may have more than one, se­lector designation or position. Neutral shall be positioned between forward drive and re­verse drive positions. In no case shall any forward drive be adjacent to any reverse drive position.
• 53.1 Low forward drive braking effect. When selected and engaged, the lowest for­ward drive position shall provide a braking effect upon deceleration and the transmission shall be so designed that automatic up­shift through the transmission range is blocked effectively for all speeds and loads within the speed range up to and including 25 miles per hour.
• 53.2 Park position. The transmission manual control sequence mechanism may be provided with a park position. When so provided and engaged, it shall initiate a posi­tive lock for the purpose of preventing the drive wheels of the vehicle from moving. Within the quadrant, the park position shall be located at the end of the sequence, adjacent to the reverse drive position.

Those rules only applied to cars (and trucks up to 10,000 lb GVW) purchased by the federal government for federal government use. However, the motor vehicle safety standards created under the National Traffic and Motor Vehicle Safety Act of 1966 — which applied to all cars and light trucks beginning January 1, 1968 — adopted basically the same requirements with slightly different wording.

 

Given Banker’s supposed concern for the many innocent victims of the “booby trap” shift pattern, you’d think he would have been overjoyed at this outcome: From 1968 on, the “safe” shift pattern he’d advocated was actually required by federal law. However, Banker’s memoir barely mentions the federal regulations, and then only to complain that “today we are designing automobiles in Washington.”

 

Banker could have taken credit (reasonably, for once) for his role in bringing those regulations about, which might even have saved a few lives, but all he really seemed to care about was what he saw as his personal victory over the hated designers of Hydra-Matic, and over GM for their slights, real or imagined, of 30 years earlier.

 

I’m not at all convinced that the old NDLR/PNDLR shift pattern was ever as much of a hazard as Banker insisted, but there was no real downside to standardization, which was long overdue. Banker didn’t exactly bring that about, but the regulatory response he helped to provoke made sure the change stuck, which I suppose was a positive outcome.

 

However, given Banker’s endless hyperbole and relentless self-aggrandizement, I find it difficult to applaud him for it. It’s telling that today, Banker is far better known for his various false and misleading claims than for his actual accomplishments.

Related Reading

The World’s First Automatic Transmission – The 1904-1907 Sturtevant Automatic Automobile (by me)
Early Hydra-Matic Users: Many Non-GM Automakers Bought This Pioneering Automatic Transmission (by me)
Automotive History: The Mysterious Disappearance of the Chrysler Pushbutton Automatic – A Government Conspiracy? (by J P Cavanaugh)