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Is the answer a good ole fashioned Over Drive?

ShadowsPapa

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I was unsure of the first year for the MOPAR lockup converter - it was actually 1978.
I know AMC's came later.
They didn't use the lockup converter on vehicles with a tow package - it wasn't common until later but the small Chrysler/Plymouth/Dodge cars used it sans-towing package starting 78.
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ShadowsPapa

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I’m not sure exactly how the mechanics of it work, but it sounds like you’re talking about something like a gear venders overdrive.

I’m not sure of the manufacturer or design, but believe it or not, my dad installed an overdrive onto both of his Model As so they can drive at more reasonable speeds when on tours. Goes from like 45 mph to 55 lol. They’re original minus a few things like turn signals and overdrive.
No, in the 60s and prior it was part of the transmission.
Gear Vendors had an add-on.
I'm talking factory Borg-Warner 3 speed transmission with OD
I remember ripping my transmission to shreds more than once and finally decided to avoid temptation, convert my transmission to non-overdrive. It only took a different output shaft and tail shaft housing.
For more money, and in the Ambassaror, you got the "twin-stick" option which was a 3 speed with a floor shifter and next to it was another stick for the OD. It was their Borg Warner electric overdrive.
They were offered in the mid-60s. Here's one online magazine's description -
Twin-Stick was Rambler's tried-and-true Borg-Warner electric overdrive system, beloved of penny-pinching fuel misers everywhere, but with a sporty twist. A second lever was added alongside the console shifter for the three-speed manual transmission.

Some guys have added the Gear Vendors add-on overdrive to their classic cars to get more mpg but still keep performance when wanted (rather than change differential gears to a higher ratio)
 

NC_Overland

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No, in the 60s and prior it was part of the transmission.
Gear Vendors had an add-on.
I'm talking factory Borg-Warner 3 speed transmission with OD
I remember ripping my transmission to shreds more than once and finally decided to avoid temptation, convert my transmission to non-overdrive. It only took a different output shaft and tail shaft housing.
For more money, and in the Ambassaror, you got the "twin-stick" option which was a 3 speed with a floor shifter and next to it was another stick for the OD. It was their Borg Warner electric overdrive.
They were offered in the mid-60s. Here's one online magazine's description -
Twin-Stick was Rambler's tried-and-true Borg-Warner electric overdrive system, beloved of penny-pinching fuel misers everywhere, but with a sporty twist. A second lever was added alongside the console shifter for the three-speed manual transmission.

Some guys have added the Gear Vendors add-on overdrive to their classic cars to get more mpg but still keep performance when wanted (rather than change differential gears to a higher ratio)
Got it. I understand why people add gear venders units, but I skimmed over your explanation and misread. Carry on.
 

ShadowsPapa

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Got it. I understand why people add gear venders units, but I skimmed over your explanation and misread. Carry on.
Weell, I wasn't totally specific, either.......

Fun fact (or boring or annoying or worthless, take your pick)
The Farmall F20 and Regular had top speeds of something like 2-2.5 mph. I can't recall, may have been the 2.5 but for those tractors with wrist-breaking steering, it was a decent speed. But with farms getting larger and more spread out, farmers took forever to get to another field. Wasted timing going on the old rutted dirt roads to get 2 miles might take over an hour.
So a company came out with an overdrive unit for them. Bolted right onto the front of the transmission between engine and transmission. Besides an overdrive, it could be shifted in and out giving you 8 forward and 2 reverse gears instead of 4 and 1.
You could also go in and replace the gears that were originally 3rd gear and make that a road gear..
 
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Jawjadawg

Jawjadawg

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The only way I know of to make the JT more fuel efficient is to lower it. That’s sacrilegious, so we are going to have to live with the fuel mileage. The JT’s transmission is excellent, and not the cause of the fuel economy.
I have no problem at all with the performance of the transmission and understand its a brick just presenting observations an wishing simply for a couple more MPG in fuel efficiency sorry I used the "e" word in reference to Wrangler or Gladiator hahaha please forgive me now if I can just get the 4WD fixed because a Jeep without 4WD is like tits on a boar hawg...
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