Transmission issues. Again.

[jberry16]

Bought a ‘21 expy with 92k miles and had tranny rebuilt August 2024, yes all in the same month. Fast forward to May 2025 it’s shifting hard from 4-5 now and from P-R. Took back into dealership and they said nothing was wrong other than it was low on tranny fluid. Said they drove it around for a few days and didn’t notice anything. How? Why? Did some digging. Apparently the previous owner took to dealership in IN for hard shifting at 73k miles and they advised to replace tranny then. Didn’t happen. So am I going to have a lifetime of tranny issues from now on? Could low tranny fluid make it shift hard? What do you suggest? Keep? Trade?

 

[BigOleFordFan]

Just an FYI, some folks in the webby-verse might take offense to the word you used in your post title

And no, it doesn't bother in the least, but I know how pol-cor & hateful some people can be nowadays....

 

[Fizzy]

Hard shift/lurch from P (especially to R) and clunky shifts 3<>5 and also around 7 are all symptoms of the poorly designed CDF drum. The only fix is to have the transmission rebuilt with the new redesigned parts.

Mine was doing the same as yours. Dealership agreed on the rebuild. They've ordered the parts, but the redesigned parts are on back order. That was 3 weeks ago so far. Not holding my breath for a rebuild to happen this summer.

 

[jberry16]

Just an FYI, some folks in the webby-verse might take offense to the word you used in your post title

And no, it doesn't bother in the least, but I know how pol-cor & hateful some people can be nowadays....

Oh geeze. I didn’t even think of that. Thanks

 

[jberry16]

Hard shift/lurch from P (especially to R) and clunky shifts 3<>5 and also around 7 are all symptoms of the poorly designed CDF drum. The only fix is to have the transmission rebuilt with the new redesigned parts.

Mine was doing the same as yours. Dealership agreed on the rebuild. They've ordered the parts, but the redesigned parts are on back order. That was 3 weeks ago so far. Not holding my breath for a rebuild to happen this summer.

Mine was rebuilt last August, supposedly with the new parts. I was told I shouldn’t have any issues.

 

[Bmac1955]

Just got mine back 6/10. When cold it would float around searching for 3 to 4 to 5. After the search of gears it would be fine. Dearship took it down and replaced CDF Drum cylinder and hub assembly. O haul valve body and a 2 spacer plates and gaskets. All new seals a piston and all new Nuts and bolts and adjusting screws. Just reading this off the invoice.
Scaned vehicle didn't have any codes. Performed Hydraulic circuit leak test where as it failed. They replaced those parts and installed the Trans. Didn't experience any issues driving when cold yesterday. So I'm good. Hope you get your issue resolved.

 

[Fizzy]

Mine was rebuilt last August, supposedly with the new parts. I was told I shouldn’t have any issues.

New parts are not necessarily the same thing as redesigned parts.

The service advisor for mine told me initially it wouldn't be the redesigned parts - just new replacement parts. A quick chat with the service manager and he clarified they are now using only the redesigned parts, but they're on a long back order.

 

[DieselMonk]

Try a transmission adaptive values reset. I might do the trick for a little while.

 

[Fastcar]

Just an FYI, some folks in the webby-verse might take offense to the word you used in your post title

And no, it doesn't bother in the least, but I know how pol-cor & hateful some people can be nowadays....

I'm thinking that some should get over themselves.

 

[BigOleFordFan]

I'm thinking that some should get over themselves.

Agreed, but it is what it is, as they say

 

[DieselMonk]

Agreed, but it is what it is, as they say

If they are going to keep on going like that, soon they run out of cobbled up letters, numbers and special characters.

 

[Bmac1955]

Ford will never run out of part numbers to supersede faulty parts replacement. It will take a Ford Parts worker to make sure the replacement part is the updated one before leaving the parts desk. That would be an issue.

 

[Fastcar]

Agreed, but it is what it is, as they say

Ahhh... not really.

 

[khammer]

I vote KEEP... but hey, what do I know? You're absolutely free to go whichever way makes sense for you.


If it were me, I'd probably opt to repair it if it ever came to that. That said, I’ve never experienced the notorious 3–5 harsh upshift that gets mentioned a lot. The only thing I’ve noticed is the occasional odd downshift while coasting or going slightly downhill and slowing—nothing frequent or consistent enough to pin down.


It’s rare enough that I can’t even tell what gears are involved, and I definitely can't reproduce it on demand. From everything I’ve read and watched, the common CDF or valve body issues usually involve a much harsher upshift or a slam into gear. That’s not what I’m feeling, so I’m just chalking it up to the classic “these 10-speeds just shift weird” explanation—at least when it comes to that downshift bump.


Now, I have felt a slightly hard shift from P to R or R to D, but honestly, that seems pretty normal for any car if there’s any tension on the driveline, like when you're on a slight incline. Again, nothing consistent enough to bring to a dealer for diagnostics.


Maybe the recent reprogramming will help. If it flashed the TCM, I’m hopeful the shifts might smooth out a bit after some relearning.

 

[jberry16]

Try a transmission adaptive values reset. I might do the trick for a little while.

Can I do this on my own at home or does a dealership need to?

 

[stslvr]

My 2020 Plat has been to the dealer twice since it hit 60k. Banging 3-4 and 7-8 hunting for gears in stop and go traffic, and shudders on slight gradients when cold. Dealer kept it for 3 days on both occasions, test drove and said they didn’t find anything wrong and since there are no codes they won’t open the tranny. I have to wait until it throws a code. Have extended warranty but you would think Ford would want to keep their customers satisfied. It’s a shame because it’s a great truck otherwise. On open highway no issues with transmission, just in traffic.

 

[ShawnP]

I'm thinking that some should get over themselves.

Nobody, who is trans, is going to have a problem with referring to a transmission as a "tranny". They will have a problem with using the term to describe someone who is trans. There is a world of difference, and they are aware of it. The original comment about some being "sensitive" to the transmission term was probably meant to be sarcastic. That, in itself, was not cool. For me, the owner of a 2018 F-150 and a 2020 Expy....I would love to get past the childish bit and get back to reading about the transmission issues.

 

[Fastcar]

Nobody, who is trans, is going to have a problem with referring to a transmission as a "tranny". They will have a problem with using the term to describe someone who is trans. There is a world of difference, and they are aware of it. The original comment about some being "sensitive" to the transmission term was probably meant to be sarcastic. That, in itself, was not cool. For me, the owner of a 2018 F-150 and a 2020 Expy....I would love to get past the childish bit and get back to reading about the transmission issues.

Agreed!

 

[Fizzy]

Nobody, who is trans, is going to have a problem with referring to a transmission as a "tranny". They will have a problem with using the term to describe someone who is trans. There is a world of difference, and they are aware of it. The original comment about some being "sensitive" to the transmission term was probably meant to be sarcastic. That, in itself, was not cool. For me, the owner of a 2018 F-150 and a 2020 Expy....I would love to get past the childish bit and get back to reading about the transmission issues.

Yeah… this thread took a weird turn. This is a forum for discussing cars.

 

[omandave]

Can I do this on my own at home or does a dealership need to?

If you have a "Forscan" compatible obdii adapter and use the Forscan software... You should be able to do the reset at home using a laptop computer. I don't recall if it takes a Forscan license or not... I don't think that it does ...
Cheers!