TCI 727 Torqueflite Rebuild Kits 1962-1970 vs 1971-1979

[LSS&B]

TCI sells 19-spline 727 rebuild kits 1962-1970
https://www.tciauto.com/racing-62-70-torqueflite-727-19-spline-non-lock-up-overhaul-kit.html
TCI also sells 24-spline 727 rebuild kits 1971-1979
Ultimate Master Racing 1971-1979 Torqueflite 727 (24-Spline, Non Lock-Up) Overhaul Kit
My Question: I thought 19-spline input shafts ended in 1966.
What is the reason for continuing the 19-spline kit thought 1970?
Was there an internal change in 1971 that necessitated a different rebuild kit?

 

[pnora]

TCI sells 19-spline 727 rebuild kits 1962-1970
https://www.tciauto.com/racing-62-70-torqueflite-727-19-spline-non-lock-up-overhaul-kit.html
TCI also sells 24-spline 727 rebuild kits 1971-1979
Ultimate Master Racing 1971-1979 Torqueflite 727 (24-Spline, Non Lock-Up) Overhaul Kit
My Question: I thought 19-spline input shafts ended in 1966.
What is the reason for continuing the 19-spline kit thought 1970?
Was there an internal change in 1971 that necessitated a different rebuild kit?

You are comparing a seal kit to a overhaul kit with clutches. At one time the kits covered all the 727 transmissions. Of course there would be extra seals, spacers, clutches, etc. Then they decided to market them with up to and after. Just to save a few bucks. Why TCI is listing them by spline count who knows. Yes there were some changes between 70 and 71. Some drums and piston changes as well as reaction shafts. So there are bushing and seal differences. A couple of bucks difference between the kits. Stupid in my opinion.

 

[GTX JOHN]

You are correct the 19 splines to 24 in 1967 in every
727 that I have seen.

 

[LSS&B]

You are comparing a seal kit to a overhaul kit with clutches. At one time the kits covered all the 727 transmissions. Of course there would be extra seals, spacers, clutches, etc. Then they decided to market them with up to and after. Just to save a few bucks. Why TCI is listing them by spline count who knows. Yes there were some changes between 70 and 71. Some drums and piston changes as well as reaction shafts. So there are bushing and seal differences. A couple of bucks difference between the kits. Stupid in my opinion.

You are correct the 19 splines to 24 in 1967 in every
727 that I have seen.

I have a 1967 BB 727, that may have some rusted internal components.
Will internals from a 1979 727 install in the 1967 727 housing?
Not talking about rebuild parts, but more like drums, planetary gears, sun gears, valve body or other parts that I might generally reuse.

 

[pnora]

I have a 1967 BB 727, that may have some rusted internal components.
Will internals from a 1979 727 install in the 1967 727 housing?
Not talking about rebuild parts, but more like drums, planetary gears, sun gears, valve body or other parts that I might generally reuse.

Far as I know they will fit. Make sure that 79 is not a lock up style.

 

[dvw]

I have a 1967 BB 727, that may have some rusted internal components.
Will internals from a 1979 727 install in the 1967 727 housing?
Not talking about rebuild parts, but more like drums, planetary gears, sun gears, valve body or other parts that I might generally reuse.

The 67 to 79 has multiple differences. First if the input shaft has a smooth non splined end for the first 1/2" or so it's a lockup. That would mean you can not use the input shaft or reaction support (back half of the pump). If it's splined all the way it's not a lock up. The reaction shaft support (or entire pump), input shaft, front drum, and the #3 thrust washer would all have to be swapped in as an assembly. The 67 uses a narrow bushing drum with 2 rings. The 79 uses a wide bushing drum that is a 3 ring design. The front planet will only work if you swap the output shaft with it. The pressure angle of the splines where the planet rides on the shaft between those years are different. I find lots of parts with rust. Most of the time the wire wheel takes care of it.
Doug

 

[LSS&B]

The 67 to 79 has multiple differences. First if the input shaft has a smooth non splined end for the first 1/2" or so it's a lockup. That would mean you can not use the input shaft or reaction support (back half of the pump). If it's splined all the way it's not a lock up. The reaction shaft support (or entire pump), input shaft, front drum, and the #3 thrust washer would all have to be swapped in as an assembly. The 67 uses a narrow bushing drum with 2 rings. The 79 uses a wide bushing drum that is a 3 ring design. The front planet will only work if you swap the output shaft with it. The pressure angle of the splines where the planet rides on the shaft between those years are different. I find lots of parts with rust. Most of the time the wire wheel takes care of it.
Doug

Hi Doug,
I'll check for the smooth input shaft area and recount the 1979 spline. I do not want to use a lockup.
I am planning to swap the output shaft, but it's great to know how the 2 years are different.
I take it that you would rebuild the 1967 components, despite the narrow bushing, as long as the rust isn't too bad?
Temp is supposed to go up tomorrow, so I will start 1967 727 disassemble. Thanks for all your help! Ben

 

[dvw]

Hi Doug,
I'll check for the smooth input shaft area and recount the 1979 spline. I do not want to use a lockup.
I am planning to swap the output shaft, but it's great to know how the 2 years are different.
I take it that you would rebuild the 1967 components, despite the narrow bushing, as long as the rust isn't too bad?
Temp is supposed to go up tomorrow, so I will start 1967 727 disassemble. Thanks for all your help! Ben

The wide bushing drum is nice. If it's not a lock up go ahead and swap. No need to count the spline as long as it isn't smooth. The way is just take all the 79 stuff as long as it has a 4 plate front clutch. Either case will work. As will either valve body as long as the neutral switch stays with the valve body as they are also different.
Doug

 

[Dave6T4]

Lock-up input shaft also has a drilled hole through it to supply pressure to the torque converter clutch.

 

[LSS&B]

Lock-up input shaft also has a drilled hole through it to supply pressure to the torque converter clutch.

Picture?

 

[LSS&B]

The 67 to 79 has multiple differences. First if the input shaft has a smooth non splined end for the first 1/2" or so it's a lockup. That would mean you can not use the input shaft or reaction support (back half of the pump). If it's splined all the way it's not a lock up. The reaction shaft support (or entire pump), input shaft, front drum, and the #3 thrust washer would all have to be swapped in as an assembly. The 67 uses a narrow bushing drum with 2 rings. The 79 uses a wide bushing drum that is a 3 ring design. The front planet will only work if you swap the output shaft with it. The pressure angle of the splines where the planet rides on the shaft between those years are different. I find lots of parts with rust. Most of the time the wire wheel takes care of it.
Doug

Hi Doug
Here is the end of the input shaft of my 1979 B200 van 727 trans.
No smooth end, so I am OK on it being non-lockup.
Also, I count 24 splines, not 23 splines like the lockup.
Thanks, Ben

 

[RemCharger]

Is the 79 trans a regular 727? Why not just build that one? Want to keep the 67 #s case??

 

[Dave6T4]

I think he wants to put the later small block guts in the earlier big block case. This will work, if he changes everything. There was a change in planet gear angles in the later '70's, so, they will not work with earlier parts. Plus, he picks up benefit of part throttle kickdown and wider front drum bushing. The newer controlled load kickdown servo can be replaced with the original '67 piece for quicker shifts.

 

[RemCharger]

I think he wants to put the later small block guts in the earlier big block case. This will work, if he changes everything. There was a change in planet gear angles in the later '70's, so, they will not work with earlier parts. Plus, he picks up benefit of part throttle kickdown.

Aha I see.. I have a buddy with a 79 440/ 727 out of an RV of some sort. But it's the shitty short bolt on yoke one. I don't see the OP verifying if it's BB or SB.

 

[LSS&B]

Aha I see.. I have a buddy with a 79 440/ 727 out of an RV of some sort. But it's the shitty short bolt on yoke one. I don't see the OP verifying if it's BB or SB.

Engine is 440
1967 Case is big block
1979 Case is small block
I don't like the narrow 1967 drum bushing. Also, the 1967 valve body has a bad rep in FBBO posts.
I drove the 1979 trans before I pulled it. Drove fine, even on WOT. Since I have a 1979 small block 727 with whatever HD components a B200 3/4 ton or 1 ton van got, it's free to eliminate these 1967 problems and upgrade to part throttle kickdown, with swapping all internal components to 1979 plus the cost of a basic rebuild.

 

[RemCharger]

Engine is 440
1967 Case is big block
1979 Case is small block
I don't like the narrow 1967 drum bushing. Also, the 1967 valve body has a bad rep in FBBO posts.
I drove the 1979 trans before I pulled it. Drove fine, even on WOT. Since I have a 1979 small block 727 with whatever HD components a B200 3/4 ton or 1 ton van got, it's free to eliminate these 1967 problems and upgrade to part throttle kickdown, with swapping all internal components to 1979 plus the cost of a basic rebuild.

Thanks. Sounds like a solid plan then.

 

[Dave6T4]

It sounds like a good plan. The truck transmission should have 4 clutch drums, front and rear, and likely a 4 planet front carrier. May or may not have accumulator spring, and 3.8 ratio kickdown lever. Make sure set screw under sprag clutch is tight.

 

[dvw]

Hi Doug
Here is the end of the input shaft of my 1979 B200 van 727 trans.
No smooth end, so I am OK on it being non-lockup.
Also, I count 24 splines, not 23 splines like the lockup.
Thanks, Ben
View attachment 1977503View attachment 1977504

That is a non lock up. Just make sure you use the pump, input shaft assy, front drum and the #3 thrust washer (looks like Mikey Mouse and may have a shim with it). You can use either set of the rear planets/output shaft assy's. Again use the entire assy's. The front planet/output shaft spline angles are different between the two years
Doug