1951 B3B 3 on the tree to floor shift conversion

[Mseacow]

Just bought my first flathead dodge truck, a 1951 b3b with a flathead 6 and 3 speed, shift on the tree. I really want to change to a floor shift. Did some quick internet searches and found that my truck could have had a floor shift 4 speed. Are the bellhousings the same? Clutch discs the same? Driveshafts the same? How about changing the top of the three speed to a floor shift? Anyway, any help is greatly appreciated!

[1949 Wraith]

The 3 speed floor shifter from the '41 to '49 3 speed trucks fit on your '51 and work fine. You just have to make a bracket to hold your later model parking brake cable.

[Merle Coggins]

The 4 speed trans has a different mounting bolt pattern, so unless your bell housing is drilled for both (unlikely) you would need to upgrade the bell housing to be able to install a 4 speed. I would be better to find a 3 speed from a '49 or earlier truck and use it instead. The only thing you would gain with a 4 speed is the Granny low 1st gear, and the ability to add a PTO. 

[bkahler]

My 51 was originally a 3-speed on the column but some PO had previously converted it to 4-speed.  The major thing I had to deal with after the conversion was the sheet metal floor pan that covers the transmission is different for the column shift so you would need to find a replacement panel that has the opening for the shifter tower.

 

 

[Tooljunkie]

I converted mine from column to floor. Much nicer to shift. I eventually swapped the whole powertrain out and plan to go through the flathead to fix the heavy blow by. Then it goes in the next one. 
the 49 3 speed top fit on my 51 column shift. Came with brake lever too so that was a bonus. 

[1949 Wraith]

19 hours ago, bkahler said:

My 51 was originally a 3-speed on the column but some PO had previously converted it to 4-speed.  The major thing I had to deal with after the conversion was the sheet metal floor pan that covers the transmission is different for the column shift so you would need to find a replacement panel that has the opening for the shifter tower.

 

 

Just cut a hole in the original floor pan for the new shifter.

[bkahler]

1 hour ago, 1949 Wraith said:

Just cut a hole in the original floor pan for the new shifter.

 

That's what the PO did.  It wasn't a pretty sight.

[Merle Coggins]

Cover it with a floor mat and nobody will know...  

[Mseacow]

Thanks everyone for the replies. Looks like the simplest way to go is to find a 3 speed from a 41-49 and bolt that in. I just found a floor shift center floor plate, so I'm getting closer. Does anyone know someone or a place that may have a 41-49 3 speed floor shift trans for sale?

[Dodgeboy49]

I changed from a 3-speed to a 4-speed in my '49 half ton largely because the 3-speed was shot. It's true that the 4-speed only gains you granny low going forward, but it also gains you a lower reverse gear. I anticipated that this would make backing a trailer easier (which it does) but I was surprised at how much it helps with regular driving as well, especially in crowded parking lots. On the flip side though, the 4-speed I found happened to be a straight-cut non synchro transmission, which means I have to double-clutch everything. I did find that I had to change the bell housing (though I think I could have drilled and tapped the original fairly easily) and also the floor pan; the pans for the 3-speed floor shifter have a slightly different hole location than the 4-speed pans. Also remember that the 41-47 transmissions had a shifter in a different location than the 48-49 transmissions. They'll work fine, you just have to have your hole in a different spot on the floor.

[1949 Wraith]

12 hours ago, Mseacow said:

Thanks everyone for the replies. Looks like the simplest way to go is to find a 3 speed from a 41-49 and bolt that in. I just found a floor shift center floor plate, so I'm getting closer. Does anyone know someone or a place that may have a 41-49 3 speed floor shift trans for sale?

The simplest way is to take the top off the older style transmission and bolt it onto your existing transmission. The '41 to '48 have a shorter input shaft than your series of transmission.

[Mseacow]

Well, this stinks. I was told last week that I absolutely could not just swap out the top of my trans to a floor shift top. 

[1949 Wraith]

10 hours ago, Mseacow said:

Well, this stinks. I was told last week that I absolutely could not just swap out the top of my trans to a floor shift top. 

If you have an older 3 speed transmission with floor shifter, the top plate will bolt on top of your '51 trans just fine and shift perfectly.

Thats what I am using on my '51.

 

The hard part is finding one.

Edited January 13, 2022 by 1949 Wraith

[Brent B3B]

10 hours ago, Mseacow said:

Well, this stinks. I was told last week that I absolutely could not just swap out the top of my trans to a floor shift top. 

Hey don’t beat yourself up, you weren’t even on this forum a week ago…. Must have joined for a reason ?

[Tooljunkie]

I cut a nice neat hole, welded a pipe to it and slid a cv boot over shifter. Sealed it up nice. 

[paul smith]

we are looking for the top of a 3 speed Dodge floor shift transmission to convert our column to a floor shifter , apparently 41 to 49 fits So i have been told , can anyone help us 

[bkahler]

19 hours ago, paul smith said:

we are looking for the top of a 3 speed Dodge floor shift transmission to convert our column to a floor shifter , apparently 41 to 49 fits So i have been told , can anyone help us 

 

Hi Paul, welcome to the forum.  It sounds like you like the floor shift over the column shift, you're not alone in that

 

Just so you're aware, parts requests are frowned upon within messages.  The preferred method of making a parts request is using the Classified section.  Parts requests are free, parts being listed for sale cost, I think $5.  Anyway, a moderator will likely edit your request and mention the Classifieds.

 

Good look in your search!

 

Brad

 

 

[paul smith]

i was looking for the information if we were correct in that the top of the floor shift would fit the top of a column shift transmission

[bkahler]

41 minutes ago, paul smith said:

i was looking for the information if we were correct in that the top of the floor shift would fit the top of a column shift transmission

 

Ah sorry about that.

 

Not having a 3-speed I haven't really paid much attention to threads talking about 3-speeds.  My suggestion would be to start a new thread titled "3-speed from column to floor shift conversion" and see what kind of response you get.  I vaguely recall people talking about that but like I said I've not really paid much attention.

 

Brad

 

[JBNeal]

5 hours ago, paul smith said:

i was looking for the information if we were correct in that the top of the floor shift would fit the top of a column shift transmission

that information has been posted earlier in this thread

[paul smith]

we have found a complete  trans floor shift from a 1940 dodge pickup , does anyone know if this will work in our 1952 pickup with orig six cyl 

[Merle Coggins]

Assuming it's a 3 speed... You may not be able to use your column shift trans cover to convert it to use the column shift, but if you're OK with having a floor shift trans it'll work. You'll just need to cut a hole in the floor plate for the shift lever to come through. 

If it's a 4 speed trans your bell housing may not be drilled to accept the mounting pattern. 

Edited September 8, 2022 by Merle Coggins

[Los_Control]

Assuming they both are 3spd transmissions. .... Many have taken the top cover from the floor shift and added it to the trans that was column shift.

 

One thing Dodge did was keep things simple. ... Assuming they are both 3spd trans .... you can probably disassemble both of them and use the best parts to build one with a floor shift.

 

I did some reading several years ago, my first truck was a 1948 3/4 ton with a 1/2 ton straight axle with a 1938 engine .... I have no idea what year the 3spd trans was.

 

Seems 1935 they did some modifications & moved the starter a few inches .... this affected the bell housing, flywheel, starter .... So you needed the correct parts to swap things from 35-36.

Your 1940 should be fine.     Dodge did everything they could to keep things simple ....

 

5 hours ago, paul smith said:

we have found a complete  trans floor shift from a 1940 dodge pickup , does anyone know if this will work in our 1952 pickup with orig six cyl 

All this post says is it is a pickup. The 4spd was a common option on all trucks these years. .... It could easily be a 4sp as well as a 3spd.

You do not offer your location in your profile .... If you are outside of the USA, often these trucks came with a 25" motor instead of a 23" motor ....

 

A whole lot of reasons why it may not work, but it probably will as a guess with the info you provided.  More info & you will get a better answer.

[paul smith]

both vehicles are pickups with orig 6 cylinder , both are 3 speed transmissions , both being 1/2 ton ,

[Merle Coggins]

Just because it’s a 1/2 ton doesn’t necessarily mean it’ll have a 3 speed. 4 speeds were also available in all light trucks.