I fixed the last post. I got distracted by a phone call.
Sort of. You get both, a larger spread, and because there are so many ratios to chose from in a ten speed transmission, the gearing is going to be super close as well. The Ford/GM 10 speed ranges from 4.70 1st gear, which is steep to a .0.64 top gear , which isn’t super tall. There have been several 5 and 6 speed transmissions with taller top gears.
By comparison the Ford/GM 6 speed that predated it had a 4.17 1st gear and a 0.69 top gear
The Ford 5 speed automatic that came before the 6 speed had a 3.22 1st gear and a 0.75 top gear
Finally the 4 speed automatic that came before the 5 speed had a 2.84 1st gear and 0.70 top gear
The trend seems to be having lower low gears but having top gear be about the same, the overall spread is noticeably broader the more gears you add. This makes axle gearing less important than it’s been in prior generations since with modern 8-10 speed automatics, you’re going get significant gear reduction just due to the very short gearing in the lower gears.
My semi educated knowledge of electric current has led be to understand that it is inefficient to carry DC current over long distances. My understanding was that oscillating current at a high frequency was vastly more efficient and generating AC was slow vastly more efficient than DC. Of course my knowledge comes from reading Popular Science magazines back in the days of Studebakers and Packards.
You’ll get a kick out of this. When I was a kid I knew one of those old time engineers. He had started with steam locomotives and wasn’t the most attentive student when training on the new diesels. He was taught to move the throttle back to the center before making transition. But he must have thought he was driving a 1940’s DeSoto, as he moved the throttle back to idle before making transition. This was a very bad thing in a 100 car freight train, as abruptly closing the throttle caused all the slack in the train to “run-in”. This means that the train went from being “stretched” to having each car’s coupler bang into the one in front of it. he would then open the throttle wide again, which caused the the locomotive to leap forward and put a tremendous strain on the couplers. Think of the “shove” of an early hydramatic shifting from second to third gear, and multiply it by a hundred. This caused him to break some couplers, and damage a few loads of freight. To bring this back to the subject at hand, i remember The Chrysler semi-automatic transmissions well, and have rebuilt many of them. I even have a quart of Gyrol transmission fluid in the garage (really just 10 weight non-detergent oil).
@old_mopar_guy. You bring back memories. My parents had a 1947 DeSoto and a 1952 Dodge with the semi-automatic transmissions. On the DeSoto it was called Tiptoe Shift and on the Dodge it was called GyroMatic. My parents still had the Dodge when I got my driver’s license, but the DeSoto was replaced with a 1954 Buick. The Buick had a three speed column shift, an OHV V8 engine, and could run circles around the Dodge with its GyroMatic and flathead 6. However, the Buick was a sedan and the Dodge was a coupe. I thought the Dodge was more cool to take on a date. I never understood why it took Chrysler so long to develop a fully automatic transmission.
You can carry dc for long distances more efficiently than ac. You just need to transmit in high voltage. The problem was they could not step up and down dc as there was no power electronics. The problem today is resistance to change and cost
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K. T. Keller, who was the boss at Chrysler following Walter Chrysler’s illness and subsequent death, was the one who prevented the development of a fully automatic transmission because he liked a clutch pedal under his left foot. The board of directors forced him to have an automatic developed, once they saw the percentage of Fords and Chevys being sold with automatics and believed many of those sales were being made at Plymouth’s expense. Chrysler had the best engineering of the Big Three in those days, and developed Powerflite, which Tom McCahill in Mechanix Illustrated called “as smooth as a bucket of warm whipped cream.”
By the way, the clutch pedal in the semi-automatics was covered in red rubber and was labeled ‘safety clutch’.
By the way, the semi-automatic VW Beetle didn’t have a clutch pedal. A girl I knew in high school drove one.
The VW systems were called Automatic Clutches.
I dated a girl that had one and I worked at a Volkswagen dealer when they were selling and servicing those goofy things. I recall that she referred to the shift lever as a “didgy-poo.”
If you weren’t accustomed to driving one and accidently barely touched the shift lever the thing would disengage the clutch and start revving the engine.
On the bottom of the shift lever was an electric contact point that would make and break a connection that operated the car’s clutch (no pedal) to allow shifting gears manually. Volkswagen called it “automatic stick-shift.”
The dealer stocked and sold many contact points (a little metal puck on the end of a wire) and the mechanics made good money replacing them when they’d “burn”, a pretty easy lucrative operation.
I hated driving them. Notice that they didn’t sell them for long.
CSA
I thought the VW clutchless system was called the Automatic Stick Shift. In the early 1960s, Rambler had a similar system called E-stick.
Back in the 1940s, Packard had an electric clutch. Hudson had some type of system that operated the clutch called Drivemaster. It seemed that a lot of manufacturers tried to figure out a way to make operating the clutch and moving the shift lever easier. Even the 1939-48 Chevrolet had a vacuum assist on the column shifter.
Thinking about having to “shift” on an electric motor, the place I was working in high school had two big pedestal floor fans. These fans were equipped with a two speed Delco motor. There were instructions on the motor that the fan had to be started on the higher speed and then, if the lower speed was desired, the lower speed could be selected. These were factory instructions and it also stated that the house fuse would blow if one attempted to start the fan on the lower speed. Occasionally, someone would forget the instructions, try to start the fan on the lower speed and blow the fuse on that circuit.
Yes and as you are probably aware, the biggest benefit is in connecting the various energy providers together into a larger network. No problem with DC but AC systems need to be synchronized to each other…
From what I’ve read, just about everyone who owned one disliked them versus the regular 4-speed manual, because they really had two forward gears for everyday use. They had a low gear for things like starting out uphill or making tight maneuvers, but most people started out in the middle gear and shifted into high gear at highway speeds, so the engine was frequently running at very high RPM.
There were so few of them made that they’re rare now, and some were even converted from semi-automatics to full manual, although they might have spent more than the car was worth for the conversion back in the day.
Yep, by comparison, the 4-speed manual was much more popular.