Truck 4-speed overdrive

Mackman

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Back in 1985 I purchased a new Dodge 1/2 ton pickup, 318 with a 4-speed overdrive trans. 3rd gear was 1:00 to 1:00, 4th was OD. Anyone have any experience putting this trans in a car? 100,000 miles later, I took the OD trans out and replaced it with a 4-speed from a smallblock 69 Barracuda that I had laying around. As I recall, the only mod I had at the time was a longer driveshaft made for the 69 4-speed.
 

moparmarks

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I have a 87 D100 /6 833OD. The trucks use the B/E tail shaft. They have a larger 5.25 bearing retainer. A friend has one in his 70 Bee. They won't handle a lot of power.
 

Cranky

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Back in 1985 I purchased a new Dodge 1/2 ton pickup, 318 with a 4-speed overdrive trans. 3rd gear was 1:00 to 1:00, 4th was OD. Anyone have any experience putting this trans in a car? 100,000 miles later, I took the OD trans out and replaced it with a 4-speed from a smallblock 69 Barracuda that I had laying around. As I recall, the only mod I had at the time was a longer driveshaft made for the 69 4-speed.
The 'A' body cars came with the shorter tail shaft is why you had to go with the longer drive shaft as Mark pointed out and he's right about not taking as much power. They are lighter though because of the aluminum case.
 

MCODECUDA

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I’ll have to investigate it closer but I have a truck 4-speed overdrive transmission that I’ll be rebuilding but I’ll be using a cast iron main case with a 307 bearing and retainer so that I can bolt it into my 64. Again I’m not 100% sure that it’s possible to change the case and bearing but time will tell.
 

Chi Town Runner

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I’ll have to investigate it closer but I have a truck 4-speed overdrive transmission that I’ll be rebuilding but I’ll be using a cast iron main case with a 307 bearing and retainer so that I can bolt it into my 64. Again I’m not 100% sure that it’s possible to change the case and bearing but time will tell.
I have the 4-speed O.D. trans in my RR. Aluminum case. Not sure what it was in originally, (truck - motorhome)
Bolted up directly to my original bellhousing (2892262) . The only thing I did was have a machine shop Bush the front of the case for the countershaft. I understand, because of the aluminum case, the weak point was the case would hog out over time were the countershaft was.
Also, I almost forgot, I had to change the rear trans mount to a later year part. Don't remember the part# but got it from Brewers. They knew which one it was. Bolted right in.

I put about 8,000 miles on mine so far with no issues.
383/438 engine at a dyno of 530 HP.
However, I don't power shift or beat it up.
I don't race it. (do "get on it" though)
Down side...VERY low 1st gear so a significant drop in RPM from 1st to 2nd. For the benefit it's livable.
Great on the highway 75MPH @ 2100 RPM with 3:23 suregrip
 
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old guys rule

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Back in 1985 I purchased a new Dodge 1/2 ton pickup, 318 with a 4-speed overdrive trans. 3rd gear was 1:00 to 1:00, 4th was OD. Anyone have any experience putting this trans in a car? 100,000 miles later, I took the OD trans out and replaced it with a 4-speed from a smallblock 69 Barracuda that I had laying around. As I recall, the only mod I had at the time was a longer driveshaft made for the 69 4-speed.
A machine shop should be able to turn down your front bearing collar to fit your bellhousing so you don't need to buy a new one. Did that on mine.
 

YY1

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I have a D100 with a mild built 440 and the trucks original 833 OD (was a 225 truck).

It's REALLY fun to drive and there's no indication that trans can't handle the power.

I don't know the rear axle gear but as noted above the first gear is really low, meaning it would be easy to render it unusable with too low an axle gear.

The worst part of driving it is the increase in "cross gate" 2-3 and 3-2 shifting.
 

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