The Stovebolt Site Forums The Shop Area Driveline '46 3-spd to 4 spd trany swap

Hi,
I am doing a frame off '46 chevy 1/2 ton restoration project. The truck come with a 3 spd trans and I located and purchased a 4 spd for it. (looking for slower back road putting around speeds) I know I will need a 4-spd floor board.
My questions are, do I 'need' to switch to the larger clutch disc and pressure plate? And what do I need to connect the rear drive shaft tube to the 4-spd trans. tail housing?

As long as I am asking questions, where can I get the emergency brake toggle levers and extenstions for my '46 half ton? (huck brakes) I do have the drivers side emergency toggle lever but I need the passengers side emergency brake toggle lever as well as the 'extensions' for both sides. I can find pics of them but no place to purchase them. New or used. Any ideas?
I fear I am missing additonial pieces for the emergencey brake (under the bed-cab area)cables/balance bar/actuator........
The cables going down to the wheel housngs I have.

You sound pretty set on the 4 speed...but..just FYI, I never use 1st gear on my 4 speed. It is the granny/creeper gear you could pull out stumps with or use when hauling a full load of shelled corn to town with.

You may want to stick with the 3 speed. Some of the gears are syncro? 4 speed froma 46 is non syncro and needs to be double clutched.

Just my $.02 after driving a 4 speed...

Just to be clear, are you talking about using an original 46 non synchro 4 speed?

The 4-spd is out of a '46 1/2 ton. I was told that the 4-spd was an option for the half ton trucks, standard in 3/4 ton trucks. Pretty much a newbie to this stuff so I don't know this as fact.
After purchasing this truck I drove it maybe 20-30 miles before begining the restoration. I just felt it was geared way to 'tall' for my intentions. ie; 1st gear 0-30 mph, 2nd gear 5-35 mpg, 3rd gear 10-40 mph.
When puttering around country back roads there just did not seem to be a 'good' gear to be in. The engine would be lugging, the truck lurching and ground spd way to fast even in 1st gear. Just got it in my head to put in the 4-sp. to gear it down a bit to make it more 'drivable' for my use.
Your mentioning of the un-syncronized 4-spd does jog my memory in regards to hearing that before. I DON'T want an unsyncronized trans! My two young (teenage) sons will be driving this as well. It is our project truck we are building together and it will be handed down to them. It is such a pleasure to work on it with them. Gives the ol'man a chance to re-live his younger days when while still in High School I street/rat rodded a '45 Ford 1/2 ton. I dropped a 413 Merc. engine with a T-10 Muncie in it. :)
Woo-Hoo!! What a ride!
I'm living proof that God watches over small children and fools. :)
I will get into this 4-spd to check on that syncro thing..........
Thanks for the heads up!

My 46 GMC has a four speed and it is non- synchro. I've thought of going to a three speed for that reason.

My first vehicle I've ever owned was/is a 1940 Chevy 3/4ton special. It has the 4 speed in it, its driven like a 3 speed except it shifts slower and down shifts take some practice. My advice is keep the 3 speed and change the gears in the rear end, OR get a later model 4 speed from the 50s that is synchro...just a suggestion

It depends on the transmission. The original 4 speed was not synchronized and actually made by gm. The sm420 (common swap) requires a change in the drive shaft. If you don't mind double clutching the original 4 speed is the way to go because of its reverse lockout.