Design of automobile transmissions

Doesn't have to go there at all for most manuals, Rick. There are exceptions, of course.

Some years ago, most American cars had manual transmissions and the shifters were on the steering column.

Some foreign cars even had the shifter coming through or from under the dash.

Those were mechanical shifter linkages for the most part, and due to the turns and convolutions, they did not have the positive feel that a shifter mounted directly on a transmission, or integral with the transmission, would have.

Now, almost all cars have gone to front wheel drive, front engines with transaxles. In such cases, the shift lever between the seats is once again a remote linkage. It doesn't have to be there at all. It has become customary.

I always thought the button-pushing to select gear was a cool idea - the Chrysler folks were big on this many years ago.

A small joystick and electro-mechanical "linkage" would be a polished answer.

I was almost certain someone would point this out after I posted. My "improved" comment would be "if the same model offers a manual that is where the shifter has to go *if they expect to actually sell any units*".

I believe you can get "creative" with shifting mechanisms for automatics and the buying public might be receptive, but if you put a manual shifter anywhere but in the center console you will not be selling very many of those cars.

It was, and it is.

Yes, from '56 through '64.

And the Neoplan and Flxble people have put a great many pushbutton automatic shifters in a great many transit buses.

In front engined rear wheel drive cars, the transmission could go either at rear of engine, or at rear axle. The later arrangement is only practical on cars with IRS, however, else the unsprung weight of rear axle is too high. To reduce unsprung weight, solid rear axle cars must have transmission forward of driveshaft.

Steve wrote:

Yeah, the pushbutton torqueflite was with us until the Naders and nanny-staters passed regulations that all automobile shifters had to be standardized. Did away with GM's unique shift pattern (something like Park-neutral-drive-low-reverse instead of P-R-N-D-(L or 2-1).

Or a Rube-Goldberg-esque abonimation. How on earth would you feed back the feel of the gears meshing to the driver so that he/she could effect a proper gear change? What you'd have with such an electro-mechanical linkage would be a "manumatic" transmission, in which case a full automatic would be just as good. Or better.

Lack of respect for other people's preferences? Who just called a Corvette "moronic" then?

Someone's gone off their meds...

You could have that "force-feedback" feature that some computer-game joytick controllers have :)

Agreed.

Maybe. Most Americans are lost when it comes to manual transmissions anyway.

F1 cars have special transmissions with button shifter, generally right on the steering. If I were to buy a manual tranny, a shifter like this would appeal to me if it did not add overengineering reliability problems.

And I WOULD buy a manual, except that I have a wife who would detest it.

Actually, popular story though that be, there was no Federal regulation that did away with the pushbutton shifter. The pushbuttons went away after '64 because driving schools were specifically avoiding automatic Chrysler products due to the buttons, and the wisdom at the time was that early exposure through driving schools, which were at the time rather universal in North America, was key to generating future brand preferences. Also, certain loudmouthed members of the motoring press, such as that lunkhead Tom McCahill, bitched and moaned continually about the pushbuttons.

Yes, GM's dumb pattern was P-N-D-L-R, and eventually a regulation was passed that prohibited any forward and any reverse driving range being adjacent to one another on the shift quadrant. That regulation, however, did not come into force until 1968. So, while industry practice swung towards P-R-N-D-L starting a few years before the regulation, it cannot be blamed for killing pushbuttons.

I don't think that was unique to GM; my Studebaker uses the same shift pattern, and it has a Borg-Warner transmission, which was also used on Fords, AMCs, (I guess back then it would have been Ramblers) Checkers, IHCs et. al. Unless Studebaker had a unique valve body I would assume the early versions of any make would have been P-N-D-L-R.

One peeve regarding this tranny - it's a 3-speed auto, but it never goes into first unless you manually select "L." I guess the engineers back then thought that customers didn't want to be subjected to the incredible pain and suffering of having to listen to and maybe *gasp* feel a 1-2 shift, but would accept underwhelming off-the-line response. Now that I believe *was* unique to Studebaker, probably because they were the only ones that could get away with it, with their light cars and torque-monster engines.

nate

It wasn't, but they were the first to use it, and for several years in various SAE papers they arrogantly informed the rest of the industry that GM would determine the quadrant arrangement, and the rest of the industry would follow it. The "no reverse adjacent to forward" regulation quashed that particular bit of GM bassackwardness.

I'll buy that...

now here's a question. AFAIK the only early automatics made were the GM Hydramatic, the Stude/Borg-Warner DG series (and the later, closely related units that were sold to Ford, AMC, IH, etc. etc.,) and the Packard Ultramatic. All three had the P-N-D-L-R shit pattern, or some close variation thereof. Who introduced the more rational, modern shift pattern and when? I actually don't know the answer, I'm just asking out of curiosity. Did anyone build an auto with a "modern" shift pattern before it became clear that a change was going to be legislated?

nate

Another consideration is the proliferation of many-speed (i.e. 5 or more) manual transmissions; for a column shift to work with a 5-speed, you need a minimum of three shift rods or cables; for a 6-speed you'd need four. Having worked on old three-speed column shift linkages, this sounds to me like a decidedly bad idea. Plus most modern manual transmissions for RWD cars have the shifter assembly integral with the transmission, you don't have a separate external lever for each shift fork anymore. This improves shift feel and precision, but precludes mounting the shifter anywhere but on top of the transmission case.

nate

Now, I was sure that my '60 Bonneville and dad's '62 Biscayne were PRNDL cars.

An advantage of P-R-N-D-... is that you can identify Sloths if you are pulling up behind some cars stopped at the lights. That telltale flash of the reversing lights shows that the Sloth has put their car into Park, meaning they will take an eternity to get moving when the lights change. So you have plenty of advance warning to select another lane or take other appropriate action.

I guess that's the one I'm remembering. But low and reverse adjacent sure did come in handy when rocking a stuck vehicle...

Your well of facts is amazing. I guess I'll have to cling to my small bit about parent-bore vs. wet-sleeve for the aluminum 225 for a long time before I catch you again... ;-)