Difference in 3 speed manual transmissions Truck/car ?????

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convx4

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What is the difference in 3 speed manual transmissions Truck and car ?

Found close to me a low mileage slant six from a 68 truck with a 3 speed manual.

I have a 66 valiant that is a slant/ auto I would like as a manual. I have the peddles and floor hump.

My question is would my car drive like a truck with this truck setup?

Whats the difference between a truck and car manual three speed?
 
Well you need to identify it. First what year is it. Crawl under there and take a couple of shots. There is only so many manufacturers PERIOD!!! of gearboxes through the years. Names such as Muncie, New Process, Borg Warner, Spicer, Eaton, etc etc. The list, really is not that long, and you won't find things like Eaton under a 1/2 T pickup

I can just about guarantee you, though, that a COLUMN SHIFT gearbox out of a pickup will have a longer tailshaft than an A body
 
You would be better off with a 1970 model year and up A-230.

I love driving mine, but some people can be silly and let them go cheap to go 4 speed.
 
I think people have put long tail manuals in A bodies, certainly '67 up would be easier.
You're gonna have to engineer the linkage so why not?
Dont know whether floor or column would be easier to sort out.
And driveshaft may have to be created.
I'm not sure I'd want a non-synchronized 1st gear tranny in mine, so check this if it matters to you.
 


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94775695_10158096820175336_7108385863762968576_o[1].jpg
 
The earlier 3 speeds did not have provisions to mount a floor shift. Column shift only. And they do not have synchro in first gear. Way back there were after market floorshift conversion kits but they were not very good.

Since you already have a floor hump and other bits in hand, you should consider finding a newer A-230 as previously mentioned by Alaskan. The floor shifter bolts up like a regular 4 speed. These were the stsndard A body trans starting in 1970 or so. If was even standard on 340 Dusters.
 
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Yep, like they said. I enjoy my 3 speed but it has no 1st gear syncro.
It is pretty stout and can take alot of abuse though. My 16 yr old learned to drive a manual with my 3 on the tree and it was easier for him than the 5 speed in my 99 Jeep Wrangler.
 
The earlier 3 speeds did not have provisions to mount a floor shift. Column shift only. And they do not have synchro in first gear. Way back there were after market floorcdhift conversion kits but they were not very good.

Since you already have a floor hump and other bits in hand, you should consider finding a newer A-230 as previously mentioned by Alaskan. The floor shifter bolts up like a regular 4 speed. These were the stsndard A body trans starting in 1970 or so. If was even standard on 340 Dusters.

I was given a truck trans that still had the bracket on it. It was pretty primitive but looked solid. I think it'd be pretty easy to fabricate something with angle iron and some nuts@bolts.

Obviously getting an A-230 with shifter is the ideal set-up but i think you could make the truck trans work, especially if you already own it. If you look at A body stuff, be aware that the A-250 is also a non-synchro first gear!
 
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So I found another slant six three speed manual set up from a 65 dart wagon. It does not have previsions for a floor mount shiftier. So were all the early a bodys floor shifts 4 speeds? The three speed manuals were column shift. The aftermarket offered a floor shifter for the three speed manual, but mopar did not. How do you identify the full synchro three speed? Can an older transmission be modified to full synchro?
 
How do you identify the full synchro three speed? Can an older transmission be modified to full synchro?

No you can not convert. Read the shop manual, and you will soon see the differences If you don't have one/ them download at MyMopar for free

The 69 book in section 21 shows the A903 and A745 (light and heavy duty non synchro low) and the 72 book shows the A903 and A230 which is the all-synchro

A90369.jpg


A74569.jpg


A20372.jpg
 
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One other thing to be aware of in your trans quest, what type of an out-put shaft does the trans have? As in, "ball and trunnion" style, slip-yoke style, or with the truck option, it may even be a short tail housing with a bolt-on yoke and 2 piece driveshaft!
 
Here's the truck thing I speak of! your auto have a ball and trunnion or a slip yoke?
100_2998.JPG
 
not worth it
There has to be a slip yoke somewhere between the trans and the rear end, to compensate for the changing distance between the yokes, as the rear suspension cycles.
What you get with that free trans is the headache of re-engineering your driveshaft. Plus you will need a longer one to start with.

Having said that;
You can convert that pictured trans to what you need, with the right parts.
 
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