I found most shops cause problems on these year model fords.  My '56 was taken to a shop and the last time it went before sitting was the late 70s early 80s.  Im not kidding they didnt even block up the bell crank with the 1/4" drillbit like the shop manual says to keep the bell crank in specified position before making the carburetor rod adjustment.  Mine was so out of adjustment I had to adjust not just the bell crank, but replace the carb linkage as well as they cut it off to make it work and I also had to adjust the rod to the transmission as it was out of adjustment as well.

1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi

I agree! Had to read it several times as it gets very technical, but explains everything very well. Much better source material than what is printed now days. 

Glad you were able to get yours sealed up and avoid the shop. Anything to keep it out of the shop is a good thing!

Kent — Round Rock, TX
'56 F-100  | '56 Crown Vic  |  '57 Fairlaine 500  |  '57 Thunderbird

Type F. I know this is a highly debated subject. We've always run Type F in all our fordomatics and never had any issues. Shifts firm but not harsh. Very positive feeling. Downshifts are no longer noticeable unless you specifically feel for them.

Kent — Round Rock, TX
'56 F-100  | '56 Crown Vic  |  '57 Fairlaine 500  |  '57 Thunderbird

Kent, I must have overlooked it, but what transmission fluid did you end up using?

Good the hear you got it sorted out. So now You know it was the Transmission Shop that caused the Problem. The Manual is very useful if You take the Time to read it. I had to replace the shifter Arm Seal on mine which involves  dropping the Valve Body. Used the Book instead of paying a Shop to do it. It is important that the Accelerator Linkage and  the Throttle Pressure Rod be properly adjusted as You have shown with Yours.

  

Update — Success!

Just got back from test driving the 'bird. It's like driving a different car now. Everything behaves like it should. Talk about a relief!

Did the pressure test before taking it off the stands (as several of you mentioned) and had to lengthen the rod several turns to get the pressure up to specs. If you baby it down the street, it'll shift about 19 mph. If you drive lightly down a residential street, about 22-23 mph. All relative on throttle pressure — just like the book says. Feels like it's about where it needs to be.

The accelerator is so much lighter feeling and easier to hold. Before it was fatiguing after a while cruising down the highway (due to binding).

Wanted to thank everyone who answered on this thread and shared their knowledge. It is GREATLY appreciated. Special shoutout to FORD DEARBORN who spent a lot of time walking me through the troubleshooting process and nailing the issue. Everything I've learned during this fiasco is going in the vault and should hopefully help me or someone else in the future. This is a great site and the level of knowledge and helpfulness is very humbling. Thanks again for helping get this old 'bird back on the road!



Kent — Round Rock, TX
'56 F-100  | '56 Crown Vic  |  '57 Fairlaine 500  |  '57 Thunderbird

Apologies on not chiming in earlier. The transmission is closed up and ready to fill. I went ahead and pulled the pinion carrier out to address a very bad leak while the car is on stands. Have all the parts, just need to get preload fine tuned and back together. 

Didn't want to fill the trans and test and then have to drop the driveshaft when doing pinion seal later and loose some ATF. Car needs quite a few other things, but trying to not go overboard with doing too much at once... famous last words.




Will be sure to update y'all when I get it back on the ground. Thanks again for everyone's help and advice!

Kent — Round Rock, TX
'56 F-100  | '56 Crown Vic  |  '57 Fairlaine 500  |  '57 Thunderbird

You're OK. FORD made it very confusing. The ATF PN during that period was C1AZ 19582-A and was retained  om all ATF progressons including the intro of TYPE - F for the 1968 model year. You had to turn the can around to see what fluid was actually in the can - Type-F Fluid (M2C33-F)



FULL INFO SOURCE - https://en.wikipedia.org/wiki/MERCON#1967_-_Type_%22F%22_Fluid

But you were a line tech in a dealership I assume. You went to draw oils from a pump out of 50 gal barrels. Most likely not FORD oil but was supplied (and equipment serviced) by a local whole-seller. Hard to say what it is you were drawing or if it had the FORD classification. Been there and done that.

____________________________

I made my earlier comment about the Type F fluid came out in 1961 from memory. So I got out my 1960-1964 Ford parts book and in the front of the book, they list all the dealer appearance and maintenance materials (e.g. things that the dealer used and sold, paint, thinners, undercoating, parts cleaner, etc.). I found the part number for a quart can of Type F fluid C1AZ-19582-A. It also came in one gallon cans and 55 gallon drums. Having worked at Ford dealerships for all those years, most of the time when you looked at a part number, the first digit "C" indicated the decade 1960-1969 and the next digit was the year that it first came out "1" being 1961, "A" was generally a full sized Ford and "Z" had to do with stocking warehouses and depots. So this is why I said the type F came out in 1961.

Thats if you can track down the API rating through changes to find a modern equal to what you are needing.  I never really looked into the API rating as there is no API rating listed in my '56 owners manual.  I think the dipstick only states "use type A transmission fluid" with no API rating on it either.  I would have to go outside and check that.

Correction, my original dipstick doesnt even say what fluid type to use, just says to check fluid level when hot.

1956 Ford Fairlane Town Sedan - 292 Y8 - Ford-O-Matic - 155,000 mi