Projects How tough is it to change from 3 on the tree to Automatic Trans?

Any trans change will require a shorter forward driveshaft. The 3sp is really short.

 

This is from a 60 shop manual. Same thing.

 

I have gone the other way on a 64 impala about a hundred years ago . When I changed from the powerglide that was behind my 327 300 hp. I put a Muncie 4 speed and got the clutch linkage from a car in the junkyard. The trans mount and the driveshaft were the same length and splines were the same from the glide to the Muncie. I came out of a crashed 63 Impala.
Remember when you could go the local junkyard and find stuff like that. You always tried to become friends with the guys that worked there so they would call you when they got something cool in.
Stopping by in the afternoon with a pizza and a six pack usually helped too.

 

Probably not what you want to hear, but you could always go with a floor shift. The only automatic that will fit, without modifying the drive-shaft (s), would be a 62-64 full sized car Powerglide, the 25 inch long one. The rest are 28 inches long and would require the front shaft be shortened, and possibly a different slip yoke used, depending on which transmission you use. How about going with the same basic trans you have only with an overdrive (yours is a Muncie 318, and overdrive is a Muncie 319). I happen to have Hurst shifters to fit all of those manual transmissions. A short shaft TH350 will need to have a different slip yoke, and the front shaft shortened; the current trans cross-member will work fine. A 200 4R trans will fit, but the cross-member has to be moved way back, and with an X-frame car like yours, may not be possible. Same with a TH400, too long and mount's too far back. A manual 4 speed will also bolt right in, but require a shortened front shaft and possibly a slip yoke change, depending on the trans used; a Saginaw 3 or 4 speed needs a fine spline, and early Borg Warner T-10 needs a course spline, like you currently have, a later T-10 (Super T-10) requires a larger diameter and fine spline yoke, a Muncie 4 speed requires a fine spline yoke, as does a TH350. If you're happy with the car, the engine and the trans, then either find the linkage you need, or swap to a floor shift. Automatics will require a different shifter also, column or floor, so you're really not any ahead by doing that, and a trans cooler. More work and more $$$, IMO. I am Butch/56sedandelivery.

 

I've never figured out why the hell when a guy asks a simple question with very few viable answers the same clowns always come out and throw out their plan for the thousand dollar fix to a hundred dollar issue.
1. since the OP hasn't had luck finding column shift linkage for the 3 speed and probably has spotted a proper powerglide donor to snag the parts from the idea came up.
2. Moriarity gave him a reliable source for correct shift linkage and I'd have to believe that he has a solid knowledge of what is in that yard. Not some BS wizard throwing out a guess but from the knowledge of having been in that yard time and time again.
3. The best thing that a "cheap" 3 speed shifter does is break a transmission when it hangs up between gears. You have to buy one of those 250+ buck ones to have one that won't hang up and now we are getting into Big bucks and the car is a blooming 4 door.

4. 4 speed because you always wanted one or that is what you always swapped to? Get frigging real, spending a thousand bucks on a 4 speed is probably about as much as he already has in the car and unless you manage the bargain deal of he week a 4 speed, correct shifter and drive shaft mods are going to cost a thousand bucks.
4. I can see not wasting money putting a Powerglide in and going to a Tubo 350 or other newer automatic but the OP's Nash wagon that looks exactly like the one my mother in law drove when I got married 50 years ago tells me that he isn't very interested in modifying his cars and wants to keep them "original" as far as what was available for that year.

That leaves one question, Will the OP be happy driving a column shift three speed after he gets the correct linkage installed? Remembering that my 59 El Camino with 3 speed column shift was a very easy driving rig I don't think it is a big issue.
That said, there are plenty of viable reasons for going to an automatic the main ones being that the left ankle, knee or hip just flat isn't up to pushing a clutch pedal. Sometimes you have to go to what works rather than what is cool.

 

Put a Hemi in it.......

IF you want to change it, it would be a whole trans (with dipstick and tube), flexplate, flexplate bolts, torque converter bolts, trans mount, new cooler lines, poss new radiator with trans cooler inside, new yoke for trans, rigging up shift linkage, rigging up a downshift cable/linkage, hooking vacuum modulator and either switching the brake pedal or just taking the clutch pedal off.

 

Hello,

In 1960, we had a been driving a 3 speed stick 1958 348 Impala since new. It was my brother’s first new car he bought with his own money. It was a fast stock car for racing in the A/Stock class and the sometimes encounters on the street. But, it was during the aftermath of our dragstrip accident, (with the 1940 671 SBC Willys Coupe) that the Impala was fading from my brother’s thoughts and futures. So, luckily, the Impala was sold to me at a discount.

My mother wanted me to teach her to drive a stick shift car and as a newly minted driver, I was able to get her to learn all of the standard steps for safe driving. But, for a little 5’2” lady, the seat was jammed up all the way to the front. The stock clutch was replaced with a heavy duty custom clutch and was hard for her to push the pedal down, but she plodded along. After several Long Beach road trips, she gave up the idea of driving a stick shift car.

Her friend had a stick shift 49 Chevy and she was used to seeing how simple the stick shift was in their trips to the weekly shopping forays. (this Impala was probably not a good sample to start, heavy clutch pedal action, powerful motor, 4:11-4:56 gears, etc. ) But, despite the bucking bronco action, she was able to drive the Impala in public back to our house.

In the weeks that followed, she offered to convert the stick shift transmission to an automatic transmission at her cost. My brother was all for it as he wanted no place in the teaching of our mom how to drive a stick. So, we had our choice of transmission conversions. The newly created C&O stick hydro was coming on strong in the drag racing circles, wheras the B&M company was a little too expensive. In talking with the C&O company, everything would be taken out and new stock mounts would be used as much possible for the stick hydro transmission.

The standard stick shift column lever was still used and converted to the stick hydro transmission lever. The cost was much less than getting a B&M Hydro and all I needed was an exchange automatic transmission to get things started. The company would do all of the custom installations. It was to be one of the first stick hydro transmissions in a stock bodied car for drag racing and daily street driving in the So Cal region. The installation was neat and functioned well for many years until I sold the Impala in the fall of 1964. So, for 4 years, it provided a faster get away from any street light challenges, and the quickness was the key to stay in front of any opponent we encountered.

Jnaki

The stock Powerglide was mentioned, but the reliability of a Hydramatic Transmission was better for the long run. But, because the Powerglide transmission was stock for your model of car, the parts for any conversion should be readily available. If you are not handy to do the conversion, there are transmission shops/hot rod shops that can handle the process. We stayed with the column shifter (including the blank aluminum insert for gear selection), but for 1964, there were already factory floor shifters to stay period correct.

 

I'm going to keep it as stock as I can. Just make it easier to shift. My Rambler wagon had a 3 on the tree that hung up at all the wrong places when driving.

 

quick question for the 58 to 64 guru's-was there ever a "short" Muncie 4-speed?if not what driveshaft did 62-64 Chevys use?On the same track what rear splines did the 62-64 Muncie have?coarse like the 3 speed and glide or fine like later?The reason I ask is if a person wants to put in a TH350 or 400 wouldn't a stock driveshaft from a 4-speed car [rare as they may be]a bolt in?

 

Do any of the vintage parts places offer repro linkage parts? They supply practically everything else for sixties Chevs. Looking at the parts book illustrations reminds me that most of the levers and rods are made of flat steel, suitably drilled and bent, and steel rods. If only a couple of parts are missing you could make them at home. If some friendly Hamber gave you the dimensions.