727 Torqueflite: Questions about 1967 Front Planetary, Thrust Washer, and Annulus

[LSS&B]

727 Torqueflite:
Questions about 1967 Front Planetary, Thrust Washer, and Annulus

1) Should I replace 1967 annulus (no drilled oil holes) with 1979 annulus (12 drilled oil holes) because of oil starvation at thrust washer between front planetary and annulus? IOW, are the drilled holes a correction to a problem with the 1967 Annulus?

2) Is it OK for thrust washer to loose most of its copper plate as long as the thrust washer is smooth?

3) Should I try to sand the rear of the 1967 4-pin/gear front planetary to be completely flat?

Details

I am rebuilding a 1967 727 Transmission

1967 Annulus (Ring Gear) is OK inside and outside, but it has no drilled oil passages like later annulus. Annulus Thrust Washer surface is smooth. However, Thrust Washer between Planetary & Annulus (Ring Gear) is smooth, but lost most of its copper plate.

I have a 1979 Annulus (ring gear) that has 12 drilled oil passages. Seems identical to 1967 otherwise. No difference in height or external gears. Rear ID at thrust washer is 2.5 inches on both. 1967 & 1979 front planetary’s install and spin excellent interchangeably in either annulus.

All input appreciated.

@dvw @Dave6T4 @oldkimmer and others

1967 Front Planetary and Annulus installed on Sun Gear

1967: Rear of front planetary. Thrust washer surface is not totally smooth
1967: Thrust washer has no copper on planetary side of washer

1967: Rear of Front Planetary
1967: Annulus side of thrust washer

1967: Rear of front planetary, lightly scored by thrust washer

1979 Front Annulus: 12 drilled oil holes between external gear teeth

1967 Front Annulus: no drilled oil holes

1979 Front Annulus on top
1967 Front Annulus on bottom

1979 Front Annulus internal gears and thrust washer surface. 1967 looks same.
1979 light duty 3-pin front planetary also pictured

 

[pnora]

Pretty sure the output shaft splines are different where the planetary fits.

 

[dvw]

I would bet the holes are a upgrade. However in my 45 years of building Torqueflites, I've only ever seen 2 planet gear bearings fail. Never seen a broken planet gear itself. Some of the tin coating worn on the thrust is normal. The planet itself has to stay with its correct style output shaft. Spline count is the same. The spline pitch angle is different. I wouldn't worry about light scoring either.
Doug

 

[Dave6T4]

I would keep the '67 setup for the 4 pinion planet gears. The back side of the thrust washer does not wear, as it just sits in place. Some wear on the front face is O.K. I usually hone these surfaces with a fine white stone to clean up any imperfections. If the holes vs. no holes is a concern, you can always drill your own holes in the older piece. I think the old B&M shift kits showed you how to do this. Don't try to swap the older 4- pinion piece into the the newer drilled annulus, since there is a difference in spline angles, as previously stated. I like to replace the fibre thrust washer between some of the input and output shafts with a brass one.

 

[LSS&B]

I would keep the '67 setup for the 4 pinion planet gears. The back side of the thrust washer does not wear, as it just sits in place. Some wear on the front face is O.K. I usually hone these surfaces with a fine white stone to clean up any imperfections. If the holes vs. no holes is a concern, you can always drill your own holes in the older piece. I think the old B&M shift kits showed you how to do this. Don't try to swap the older 4- pinion piece into the the newer drilled annulus, since there is a difference in spline angles, as previously stated. I like to replace the fibre thrust washer between some of the input and output shafts with a brass one.

Hi Dave,
I'm glad to keep using the 1967 planetary and thrust washer. That's good news!
I understand that the 1967 and 1979 output shafts are different.
I understand about not using the 3 gear 1979 planetary because it does not match 1967 output shaft.
I don't understand why I can install the 1967 planetary into the 1979 annulus and it turns easily. Why isn't it binding as the gear teeth engage the inner teeth of the annulus, if the pitch is different?
Thanks, Ben

 

[pnora]

Hi Dave,
I'm glad to keep using the 1967 planetary and thrust washer. That's good news!
I understand that the 1967 and 1979 output shafts are different.
I understand about not using the 3 gear 1979 planetary because it does not match 1967 output shaft.
I don't understand why I can install the 1967 planetary into the 1979 annulus and it turns easily. Why isn't it binding as the gear teeth engage the inner teeth of the annulus, if the pitch is different?
Thanks, Ben

Its not the gear's that are different. Its the splines where the

Hi Dave,
I'm glad to keep using the 1967 planetary and thrust washer. That's good news!
I understand that the 1967 and 1979 output shafts are different.
I understand about not using the 3 gear 1979 planetary because it does not match 1967 output shaft.
I don't understand why I can install the 1967 planetary into the 1979 annulus and it turns easily. Why isn't it binding as the gear teeth engage the inner teeth of the annulus, if the pitch is different?
Thanks, Ben

This is where the pitch is different.

 

[Dave6T4]

Hi Dave,
I'm glad to keep using the 1967 planetary and thrust washer. That's good news!
I understand that the 1967 and 1979 output shafts are different.
I understand about not using the 3 gear 1979 planetary because it does not match 1967 output shaft.
I don't understand why I can install the 1967 planetary into the 1979 annulus and it turns easily. Why isn't it binding as the gear teeth engage the inner teeth of the annulus, if the pitch is different?
Thanks, Ben

I have had them where the two pieces interfered, when I was mixing and matching parts. Perhaps annulus was newer, yet??? I am not sure what year the gear angle was changed.

 

[Rebelrouser]

727 Torqueflite:
Questions about 1967 Front Planetary, Thrust Washer, and Annulus

1) Should I replace 1967 annulus (no drilled oil holes) with 1979 annulus (12 drilled oil holes) because of oil starvation at thrust washer between front planetary and annulus? IOW, are the drilled holes a correction to a problem with the 1967 Annulus?

2) Is it OK for thrust washer to loose most of its copper plate as long as the thrust washer is smooth?

3) Should I try to sand the rear of the 1967 4-pin/gear front planetary to be completely flat?

Details

I am rebuilding a 1967 727 Transmission

1967 Annulus (Ring Gear) is OK inside and outside, but it has no drilled oil passages like later annulus. Annulus Thrust Washer surface is smooth. However, Thrust Washer between Planetary & Annulus (Ring Gear) is smooth, but lost most of its copper plate.

I have a 1979 Annulus (ring gear) that has 12 drilled oil passages. Seems identical to 1967 otherwise. No difference in height or external gears. Rear ID at thrust washer is 2.5 inches on both. 1967 & 1979 front planetary’s install and spin excellent interchangeably in either annulus.

All input appreciated.

@dvw @Dave6T4 @oldkimmer and others

1967 Front Planetary and Annulus installed on Sun Gear
View attachment 1996654
1967: Rear of front planetary. Thrust washer surface is not totally smooth
1967: Thrust washer has no copper on planetary side of washer
View attachment 1996655
1967: Rear of Front Planetary
1967: Annulus side of thrust washer
View attachment 1996656
1967: Rear of front planetary, lightly scored by thrust washer
View attachment 1996657
1979 Front Annulus: 12 drilled oil holes between external gear teeth
View attachment 1996658
1967 Front Annulus: no drilled oil holes
View attachment 1996659
1979 Front Annulus on top
1967 Front Annulus on bottom
View attachment 1996660
1979 Front Annulus internal gears and thrust washer surface. 1967 looks same.
1979 light duty 3-pin front planetary also pictured
View attachment 1996678

 

[Rebelrouser]

When mixing and matching parts the knowledge level goes way up. I like to keep it simple, when messing with the older torqueflites, I keep the case and buy a newer core transmission and swap out the internals, that way you get all the improvements. I especially like the wider front drum bushing and the matching pump. I have had very little issues with planets, the ones I have had been long use high HP cars like over 800HP. The torqueflite is a great transmission and very strong.

 

[dvw]

There should be no issue using the 79 annulus gear with the 67 planetary carrier. But to be honest I see no reason to do it. The holes aren't that big a deal. They allow oil in the annulus an additional escape route from the front planet to the inner teeth of the rear clutch frictions. This clutch is always applied when the vehicle is stationary. So there can't be a huge benefit.
Doug

 

[LSS&B]

OK, so I can use the later annulus, but with little benefit.
4 Gear planetary is OK to reuse, given gears and vertical gear play are OK
Thrust bearing is OK to reuse.