1964 Pushbutton 727 BB Trans Rebuild

[threewood]

It's been sitting around long enough and I'm bored. Finally getting around to rebuilding the 64 transmission I picked up from Dryheat aka Jim several years ago. I don't have a big block to put it on...yet.

I guess my first question is...should I keep the ball and trunion? I've got the driveshaft for it. Rebuilt it a few years ago so it's in good shape. Is there an aftermarket slip yoke that is made for it?

Rebuild is going to be simple. TF-2 shift kit, new Alto clutches. Both bands are the solid type and in good shape, CRT band applies and billet L/R servo, new seals and bearings. Both planetaries are 3 gear and are in usable shape.

I have a few parts and bolts in Evaporust to clean up while waiting on parts.

 

[Geoff 2]

YES! Keep the ball & trunnion. Not only is it very durable & reliable, it has an important safety feature....
Should a conventional front U joint break & fall to the ground, car moving, think of the consequences.
This is virtually impossible with the B & T.

 

[dvw]

No need for Alto frictions or billet servos in this application. Raybestos tans or Borg-Warners will be fine. The ball & trunion will work in all but the most severe application. You can swap to a slip yoke. But the swap would require an output shaft and tailshaft housing from any 1965 only 727. The converter splines of all push button (and 66 non push button) are odd ball. If you want to use any readily available converters the input shaft, reaction shaft support, and pump gears need to be swapped. 67-70 parts will bolt in. 71 and newer non lock-up wide bushing parts will work as well but require the matching wide bushing front drum as well. For what its worth my racecar's push button trans has 10 years of low 9 high 8 second runs using stock servos.
Doug

 

[Lefty71]

I guess my first question is...should I keep the ball and trunion?

I too have heard by more than a few people that keeping the ball and trunnion is not a bad idea.... Remember that all Max Wedge cars started their lives with them, and breakage was not a concern. If you do decide to change to slip, you can only get the parts you need from a '65 trans....anything later is not going to work. They made pretty major changes from '66 on to the tail and shaft once the rear pump was gone. Spline angles become a concern as well when swapping parts, so make sure your shafts match the planetaries if you go swapping parts. Also, worth mentioning, I have read but not had any direct experience with yoke issues. If you pick up a '65 trans for parts, try to grab the matching front yoke... they say that you can get or cause leaks if you dont have the right vented yoke for a '65 trans. Sure sounds easier to just rebuild the '64 lol.

Good Luck, Lefty71

 

[dvw]

The later yokes fit the 65 output shaft. However some are too long and bottom out on the expanded ridge just forward of the splines. See 2nd shaft from the top in the pic. Easily remedied with a chop saw.
Doug

 

[threewood]

The later yokes fit the 65 output shaft. However some are too long and bottom out on the expanded ridge just forward of the splines. See 2nd shaft from the top in the pic. Easily remedied with a chop saw.
Doug

View attachment 1445992

Nice photo! I'll keep the ball and trunion.

 

[Lefty71]

The later yokes fit the 65 output shaft. However some are too long and bottom out on the expanded ridge just forward of the splines.

Good info, thx. If I'm remembering right, that ridge is supposed to have an Oring, which it stops there. .....and the '65 only yoke should be machined round in that area (no spline) to accept the oring.... and that's why the yoke had the small cap with the tiny hole in the rearward end to vent that joint when the yoke slides in and out. Must not have been the best way, because they got away from it the very next year.

 

[threewood]

I need to pick up some glass bead to clean the case and tail housing. I also ordered a new output shaft bearing as the one in there was questionable. I have the front pump housing soaking in the evaporust.

Couple of part stamps...

 

[threewood]

 

[dryheat]

Looks like it's in pretty good shape. Maybe I should have kept it.

 

[threewood]

Looks like it's in pretty good shape. Maybe I should have kept it.

It is in good shape. It got wet at some point after the move and before my shop was built so it got surface rust. Internals are nice.

 

[threewood]

Got the new bushing and seal in place. Took apart the rear drum, 10 springs. Clutches and steels look good. But I have new Alto reds soaking in ATF for install.

 

[threewood]

Putting it back together today. I had planned on welding a transmission fixture but didn't so I'll put it together on the bench.

Rear pump went back in, very little wear. Overrun clutch went back in. It was tight in the case and the parts looked new. Cleaned and re-installed.

 

[threewood]

In went the output shaft with new seals.. there is a ball bearing that drives the rear pump.

Low/reverse band needs to go in first with the strut. I put a new oring on the pivot shaft and added rtv to keep it from weeping.

 

[threewood]

 

[Geoff 2]

Happy days!

 

[threewood]

So I got the pump housing installed and the tail shaft put in with a new bearing. I still need to measure end play but it feels pretty good.

I checked both servos and clutch packs with compressed air and they all are good to move on to the valve body. TransGo TF2 kit going in.

 

[threewood]

I'm just waiting for the tailshaft seal but it is all done.