New member. I have a 69 F100 with the stock manual transmission. Looking to update it to a automatic trans w/floor shifter. What tranny do you recommend and any secret stuff to look out for when starting this project? Thanks.

P.S. Most of my hobby work has been on later model fords, so this is my first experience with an older Ford pickup.

The main limiting factor will be what motor you have. It also depends what you want to do, if you want overdrive and that kind of thing. The C6 is commonly the go-to trans, and has pretty much every bell housing style available.

Thank you sir. It's got the 360 with 2 four barrels right now. Going for a street rod type thing most likely. Do you know if I would need to change the length of the drive shaft?

Well, if you went C6, I am sure you do have to change the driveshaft. If you go C4, then they are a direct trade I think, but can't outright validate that. That also is assuming you have a 3 speed manual.

You will need more than just the transmission alone though, as there is a rod that goes from the trans to the carb that needs to be hooked up, and rarely comes with the transmission. You would need the flexplate and bolts for the crank shaft, as the manual trans bolts will be too long. You will need to have an automatic radiator to have the cooler tank in it. You then will need the steel lines to run to the radiator. Next headache will be the speedo gear, you will need to know what rear axle ratio you have so that you can see what speedo gear you need to make it somewhat accurate. You will need to be sure and get the dipstick tube for the trans as well.

Upon install, it is critical to be certain the converter is seated all the way into the pump. If you don't, you will end up damaging the pump and/or case if you try to pull it in to the block with the bolts. You also must be careful to get the converter studs lined up in the hole for the flexplate. They only go in one way, and it is easy to get them wrong by lining up all but one.

outstanding information. Thank you sir it is much appreciated. I will keep you posted to how it goes.

I did a little more digging. Looks like my truck has the t-18 tranny in it currently. Could you tell me what tranny might be the easiest swap to get a more current/useful transmission? Right now I'm willing to go either manual or auto. Whichever is the easiest to swap.

Sorry for the repeated questions and thank you for your time.

If you are wanting to upgrade to overdrive, it isn't overly simple, as the last FE motors were made in 76, and they never had a common bell with any other Ford motor. There are adapter plates available, but they cost about as much as the transmission or more. Your next option is to look for an add-on overdrive, which again isn't exactly cheap...

The T18 is a durable trans, and its newer version T19 is dang near bullet proof. The NP435? is also common. It depends on what you are wanting to accomplish by changing out the trans.

The C6 used with FE engines (360/390 etc) will not fit any other engine size. There is no 'converter' housing, as it's made as part of the trans case.

1973/76 C6: There is no speedo DRIVE gear, as it's made as part of the output shaft.

No Ford car or truck with a FE engine came w/a C4.

Depending on how much $$$ you want to spend maybe you could look at dropping in a 351 and zf 5 speed - adding power to the 351 is going to be cheaper than with the 360