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Looking to buy my wife a V6, and the descriptions claim "5 speed with overdrive". Does this mean there is another gear above #5? Never noticed it with my own.

 

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Used to mean and apparently still does that the final transmission output ratio in 5th gear is greater than 1:1 (5th gear - 0 .756 input shaft rev to 1.0 output shaft rev.)
From a 2007 post:
first- 4.235
second- 2.360
third- 1.517
forth- 1.047
fifth- .756

overall diff ratio- 3.08
 

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So, it is still five gears. Right? Friggin ad copy writers posing as engineers. Eh?
 

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So, it is still five gears. Right? Friggin ad copy writers posing as engineers. Eh?


Yep - the V6 comes OEM equipped with an "overdrive" fifth gear! Not so the 4.3 4-cyl. with its 4 gear trans and the 4th gear isn't an overdrive gear, as I recall.
 
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As I recall back in the day automatics had 3 speeds...auto makers then added a 4 hear and called it overdrive...nothing more than a marketing rouse...ever notice cars used to have 1 2 D the the O over the D for overdrive...my v6 just has 1 2 3 4 D...
 

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I had two V8 Fords with 3-speed steering column manual shift and electrically-engage-able overdrive, which also could be locked out manually. The overdrive reduced engine RPM and could be engaged in any gear., so theoretically that transformed the car to having a 6-speed gearbox. Unfortunately Ford mounted the large solenoid which actually engaged the overdrive low toward the rear of the transmission. Drove along our paved rural Minnesota road in spring, drove over one the legendary frost heave humps and that tore out the solenoid unit along with the mounting bolts and bolt holes, so went to an auto salvage place, got a replacement trans for $25 and installed it. Thereafter I avoided roadway frost heave humps!
 

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So, it is still five gears. Right? Friggin ad copy writers posing as engineers. Eh?
Agreed. The ads are aimed to impress buyers who don't have the slightest clue what gears are let alone overdrive ones. :confused: I wonder how a salesman at that dealership would try to explain it?
 

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to be fair, that's relatively standard marketing terminology
 

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In the early days, some manufacturers claimed to have overdrive in their vehicles, but it was actually just a lock up torque converter.
 

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to be fair, that's relatively standard marketing terminology
Is "standard marketing terminology" ever fair?
 

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Discussion Starter #11
I had two V8 Fords with 3-speed steering column manual shift and electrically-engage-able overdrive, which also could be locked out manually. The overdrive reduced engine RPM and could be engaged in any gear.,[...]
I think, but am not sure, that the Lincoln line had it first. A genius friend in Maryland installed one in his '56 Ford Crown Victoria (with a hell of a modified engine.) It was great for street racing from a rolling start. He would roll down his window, hit the overdrive button which caused a subtle shift. The expressions on the other guy's face was priceless. Then he would shift down manually and blow away.
 

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I think, but am not sure, that the Lincoln line had it first. A genius friend in Maryland installed one in his '56 Ford Crown Victoria (with a hell of a modified engine.) It was great for street racing from a rolling start. He would roll down his window, hit the overdrive button which caused a subtle shift. The expressions on the other guy's face was priceless. Then he would shift down manually and blow away.

I wouldn't be surprised if Lincoln had a more sophisticated system than I had on my Fords, and my father had a Ford with overdrive as well. With ours, there was a T-handle pull mounted under the dash - pulling it toward the driver locked out overdrive. To engage overdrive the handle was pushed in and the car's road speed had to be at least something like 25mph (if I recall), the driver had to take their foot off the throttle, and then overdrive would engage. Also if I recall Ford said that using overdrive reduced engine RPM by 1/3 - my memory is somewhat fuzzy about that.
 

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One of my Volvo P1800s had electric OD but it was locked out until 4th gear. I bypassed that switch and connected the OD solenoid to one of the steering wheel stalks. When getting ready to pass someone I'd shift to 3rd OD, effectively 4th, and use the stalk to cancel OD giving me a passing gear w/o shifting. Worked great!
 

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Seems like a normal description to me.
 

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Have you guys noticed the "half gear" (as I like to call it) on our cars. Not sure if the V6 does this, but the i4 does as well as a few other cars I have driven in the past.

Seems like the car will shift into and out of this "half gear" before changing a full gear, as if there is a high and low for every gear. For example, cruise at highway speed give it a little more gas, and the RPMs jump up a couple of hundred revs, but it does not jump a full gear, which is t least 500 RPMs. Take your foot off the gas and the rpms will bump back down. IF you step on the accelerator any further it will then do a full downshift.

I have noticed this on cars for many years now, and don't think I am imagining it.

Anyone have more info?
 

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^^^ You've just described the lock-up clutch working. When the turbine side of the torque converter reaches some critical threshold speed ratio with the impeller side - the torque multiplication falls rapidly, and a lock-up clutch is applied to increase efficiency. This is usually indicated by a slight drop in RPMs at steady state speed. If you step on the accelerator gently, it release the lock-up clutch - revs increase. Step on the accelerator more, and you get a kick down to the next gear.
 

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0:)
^^^ You've just described the lock-up clutch working. When the turbine side of the torque converter reaches some critical threshold speed ratio with the impeller side - the torque multiplication falls rapidly, and a lock-up clutch is applied to increase efficiency. This is usually indicated by a slight drop in RPMs at steady state speed. If you step on the accelerator gently, it release the lock-up clutch - revs increase. Step on the accelerator more, and you get a kick down to the next gear.
Thank you for the explanation.
 

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Yep, a half gear is exactly how I describe it when the TC unlocks. And fishexpo described its implementation quite well.
The only time it's important to understand it is when towing a heavy trailer. I've actually had a TC clutch fail on a Mits Expo when the TC tried to relock after passing a vehicle. That's why it's best to tow one gear down from normal. TC stays locked.
 
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