Beast or stock sun shell?
My question for you guys is what else would need to be changed to run the GM sunshell , or is it a straight swap?
My question for you guys is what else would need to be changed to run the GM sunshell , or is it a straight swap?
The Best V8 Stories One Small Block at Time

This is a picture of the new Reaction Carrier Shaft (on left with torrington bearing) and the older one which uses the four-tab thrust washer. (Note this is upside down from how they are installed when building the trans.)
It appears that the older one could be machined, but the new one is available on ebay and probably directly from the dealer. The same Internal Ring Gear is used with both and easily swapped.
I find there is zero input shaft free play when using the Beast, and this is the reaction carrier shaft with the Torrington bearing.
I tried to use the thinnest production selectable washer behind the front Torrington (that the stator rests upon), and still there is no input shaft end play.
I reverted to the production GM sun shell, put it all back together with the original #69 selectable washer, and, Voila, correct input shaft end play.
So the difference is definitely the Beast sun shell thickness, which is moving the entire input section forward so much that there is no longer any input shaft play.
What to do????
These units stock almost always have excessive end-play.
The most common cause of low end-play is due to a mis-build or after-market parts not taken into account.
The reaction sun-shell is part of the rear section. The rear section can and will effect the front end-play.
Re-check both the rear section stack outside the case and the rear and front sections combined.
You will most likely find a mis-build. You may even find that not all the 3-4 clutches or reverse input clutches are engaged.
Update us with the rear section end-play and the front after rebuild, ETC...
I removed the entire input section, ring/planet, and snap ring, removed production shell, and removed OE plastic washer on the roller clutch inner race.
I applied TransGel to rear of The Beast and stuck the provided plastic washer onto rear face of The Beast, and installed The Beast, and the snap ring.
Reinstalled the ring and planet.
I removed the input drum, Torrington, and the selectable washer, installed just the Torrington, put drum back onto input housing, reinstalled the input section, put the gasket back on, and the pump, and installed 2 pump screws, verifying plenty of end play when finger tightened... no band.
I then installed remaining bolts, and torqued them to spec.
Next, I measured the total end play, with no selectable washer installed.
I took that distance, less 0.020" (0.016" minimum + 0.004"), and surface ground my #67 production washer to that thickness, holding the washer on magnetic chuck, spraying coolant while taking the washer down by a couple of thousandths per face pass side to side.
Then I cleaned the washer, removed the input section, lifted off the drum, put the washer under the Torrington, realigned the drum, and re-seated the input section into the body, verified that the drum was about 1/16" below the pump mound face, and seated the pump, checked clearance, and put in 2 bolts as before, fingered them down, and still nice clearance, so installed the other screws.
End play is now fine.
Now, I have one sniggling questionl... That plastic washer supplied with The Beast, it is pegged into the rear face of The Beast, and facing onto the roller clutch inner race. This means the inner face face is now the running face against the washer, whereas, with the OE washer tabbed into the roller clutch inner race, the running face is the rear face of The Beast against the OE plastic washer forward face.
Considering the finish difference between The Beast (or any shell, for that matter), is much finer than the face of the roller clutch’s inner race.
Is the plastic washer likely to be worn away running against the roller clutch inner race?
Thanks for your commentary above, vorteciroc, the clutch plates were all splined properly, and the lack of end play was definitely due to the selectable washer and added thickness of THe Beast.
Last edited by keith20mm; Feb 14, 2020 at 03:26 AM.
Congrats on completion and for taking the time to sort this out properly.
I believe you stated that, a few thousandths (0.002" - 0.003") were removed from both sides of the selective washer.
I can honestly say, that I have found the need to do something like this incredibly rare (especially with a #67 selective).
I nearly always end up tightening end-play throughout the entire transmission with selective shims from Sonnax.
I stopped building these transmissions with "The Beast" shell about 8 years ago, and switched to the Sonnax part.
I have heard "The Beast" shell has suffered even worse in quality since then... however I believe the thrust washer to be the same.
The plastic thrust washer included with "The Beast" reaction sun-shell tends to hold up fine.
That particular thrust location usually does not see major stress relative to other thrust surfaces within the transmission.
Sonnax adding a torrington thrust bearing in that location is nice, but completely unnecessary.
The THM350 transmission, that all of this is based on actually would see relatively more stress in that location and would benefit from the torrington bearing.
https://a.co/d/2etMV0B
what do you guys think of this? $55 for a beast shell
42298B
https://a.co/d/2etMV0B
what do you guys think of this? $55 for a beast shell
42298B
Number is right at the bottom of his page
Regarding your post, be careful ordering off Amazon. Although that one is from WIT, which is a good vendor, sometimes parts say they are AC Delco...arent AC Delco.
Number is right at the bottom of his page
Regarding your post, be careful ordering off Amazon. Although that one is from WIT, which is a good vendor, sometimes parts say they are AC Delco...arent AC Delco.
But as you say the titles will say GM SONNAX and more with actual right part numbers very misleading. But the manufacturer listing I have found you can count on .
And yes I get alot of stuff on AMAZON that actually comes from WITS as I can get sometimes a much much better price than I can through my sales person at WITS and they are aware but its due to pricing / volume structure they have and are unable to price match which frustrates my sales person.
Sorry If a Hijack .












