Technical 1951 ford f1 transmission swap

i just bought a nice 51 f1...

i want to trash the non synchro 4 speed with a synchronized 4 or 5 speed...

just wondering which is the best easiest reasonbly inexpensive way for a quick change out...

all ideas welcomed!!!

tyvm

 

I am going to use a 84-87 F150. Its fully synchronized, 3 speed with overdrive and is close to a bolt in
$90 at the U PullIt

 

thanks much. can you use the same drive shaft, "as is"? i will start looking for that trans...

 

Driveshaft will be too long, the OD has a long tailstock like the toploader it is based on.
BTW, do NOT get the trans that has internal shift linkage, they are crap. If it has a normal-looking shifter with open linkage, grab it. You can tell an OD from a normal 4-speed by looking at the 3-4 shifter arm on the side, if it's pointing the opposite way to the 1-2 lever, that's the one you want. Of course if you want a "real" four speed, the toploader is an excellent transmission but you will pay way more for one.

 

thanks much!

 

will the cross member need to be modified for this swap?

 

Nice truck. I assume you have the flathead V8 in the F-1? If so, the T-5 is a great trans to use with that. The S-10 version with the forward shifter location is what you want (so do many others, so a bit in demand). Get an older one with mechanical speedo. You will need an adapter to mount the trans to your bellhousing, but several choices there. Search HAMB for T-5 conversion with flathead and you will learn all you need. You will have to modify the driveshaft for length, and need to T-5 yoke.

Others have done this swap and are real happy with the T-5 trans shifting vs the stock non-synchro box.

 

You could use a '49 - '51 Merc OD ... it's bolt - in & has a personality ...

 

All of the transmissions mentioned above will require serious modification or removal of the stock F-1 trans cross member. I used the T-5 behind the flathead in mine. And while I love it, it was neither cheap or easy...

 

As RMR&C stated there are few bolt in options for your truck. The only true bolt in using your existing drive shaft is the heavy duty three speed as used in 42-52 1/2 ton pickups. The next easiest is the light duty three speed floor shift as used in 42-50 1/2 ton pickups. The u-joint on the transmission end is different between the heavy duty and light duty transmissions. All other transmissions require cross member butchering, particularly the 49-51 Mercury overdrive transmission.