hopefully in the not too distant future i am going to be building a 727 and was wondering if anyone had the part numbers for the bearings used. it's been 30 years since i built a TF so i don't remember their construction. this is not a high power application but i figured being as i have the ability to do the required machining i would rollerize the build. correct me if i'm wrong but there would be three thrust bearings involved and one radial needle in the output support? i did look at the archived thread regarding this but was thinking there might be some updated info available such as exact part numbers, vendors and the required modifications. thanks

The Torrington bearing numbers for the rear support are B-2414 (7/8") or B-2416 (1") or B-2420 (1 1/4") depending on the length you intend to use. If you intend to put a lip seal at the front of the bearing bore the 14 or 16 are necessary, without a seal the 20 can be used. By adding an "O" to the part number you get the needed oil hole. The last time I tried to get the ones with the oil hole they were discontinued but that's been a couple of years ago.

thanks John it looks by the bearing numbers the second two digits represent the length in 16ths of an inch. not being versed in this mod (or TF in general) i was wondering about lubrication and thought it might just be a splash lube deal. you say there's a hole required (can it be added) and why would you want to install a seal in front? thanks

There's some debate as to whether or not the roller bearing bleeds off lube pressure to the gear train, by sealing both ends of the bearing full lube pressure is sent to the gears.

If a bearing without the oil hole is used the seals would be omitted.

Thanks again for your time John, i fully understand the idea and agree. one thing that made me wonder after thinking about it though is that those type seals aren't meant to retain any real pressure, i think they're only rated around 2-3 PSI but they seem to be what people have used.

Roller thrust bearings are the GM TH350 Pump stator bearing 1976-86, Delco P/N 9436851, OD=2.900", ID=2.110", thk=0.140". You can also buy these from www.bulkpart.com, P/N 44211C. These replace the factory thrust washers. You have to machine the faces of the planetaries and the front annulus gear. Total gear train endplay should be about 0.008" - 0.015". The annulus gear is very hard, ~60 Rc. The planet pin axles are hard and it is difficult to machine the soft aluminum along with a hard pin at the same time. May have to use a carbide cutter to grind the pins down enough to make a clean face cut on the aluminum. The rear support can be done as John suggested. You can also machine off the low/rev drum hub and install a roller bearing in the low/rev drum with a reducing bushing. Torrington B2410 bearing or SCE INA 2410. You install a Torrington bearing in the narrow rear support with it hanging out the back slightly. It will obstruct the oil feed hole from the rear cooler line slightly. You have to clearance the front of the park gear for clearance.

John

Thanks John R, i figured you wanted to tighten up the endplay with a roller setup and i'm thinking those are similar numbers to what is used when installing the needle thrust in a glide. don't need stuff slamming around on the hardened parts.

I'll keep this info. Thanks!!

For the audience, this is what I have done rollering the rear support, but not the rear drum.
See attached.

And here are my recommendations to improve oiling the rear drum (if not rollerized), if you add a bearing to rollerize the shaft to the rear support.

The groove labeled in blue is covered by the case when the support is installed, so the groove becomes an oil passage.

And this shows the new groove (labeled in blue above), from the other side intersecting the source of the fluid (large hole). This larger hole is fed from the case via the cooler return passage (low pressure).

You can see the smaller oil hole in the bearing (-OH). This allows the cooler return fluid to go into the bearing, and then into the shaft where it goes to the planetaries, etc.

thanks again to everyone and please feel free to keep adding information

Ok been busy on this one. HEMIFRED hooked me up with a core and cheetah valve body (thanks Fred). tore it down cleaned it up and started the mods, here's a mess of parts

case cleaned, glass beaded and ready for mods. i always fill all threaded holes with bolts, getting the beads outta threads is a problem.

setting up the shell for the cheese treatment. used a precision bar and digital level to get it aligned. there's eight lugs 45° apart so that's where i'll start with eight holes on the outside.

using an electronic edge finder to get the center of the lug (using center feature on the DRO)

ok last hole on the outside, i hate working with steel what a mess

laid the super spacer down to do the angled holes. used a vernier protractor to find the angle (i used 24°) to tip the mill head to.

ready to do the angled holes, there's eight of them as well offset 22.5° from the outer holes so they fall in the center of the outer holes

ok that's all the holes it's getting