We do have a tech section of the forum and guess which is the first TSB?
http://www.348-409.com/forum/threads/63-t-10-front-bearing-retainer.27124/
http://www.348-409.com/forum/threads/63-t-10-front-bearing-retainer.27124/
My 63 Impala SS restoration
- Thread starter 63409
- Start date
63409
Well Known Member
The TSB that you posted suggests to change to a cast-iron retainer part number 604932
63409
Well Known Member
I was looking over the TSB more closely and it says cast iron retainer part number 604932 as a replacement for the aluminum retainer except for 409 engine?
http://www.348-409.com/forum/threads/63-t-10-front-bearing-retainer.27124/
http://www.348-409.com/forum/threads/63-t-10-front-bearing-retainer.27124/
The T 10 that I rebuilt a wile back I use the bearing retainer from a old non synchronized 3 speed.
63409
Well Known Member
https://www.riversidegear.com/munci...963-only-muncie-4-speed-bearing-retainer.html
NOS 604932 cast iron bearing retainer
PRICE
NOS 604932 cast iron bearing retainer
PRICE
I have this one from one of the three speeds, your welcome to it if it's not a numbers thing that you are looking for.
I just checked this one to see if it fits a muncie case that I have setting around and the bolt pattern is not the same. Muncie has a larger bolt pattern.
63409
Well Known Member
My 63 Borg and Warner transmission was a one year only, I also have a Muncie early 64 transmission where I can cross check the iron retainer bolt pattern. I am a numbers guy so I guess if I can find the Muncie 604932 cast iron retainer that should have the right diameter to fit the 553 bell housing and bolt pattern for my Borg and Warner that will be the part I want.
Once you find a retainer that will bolt up, you will want to check the front bearing retention design- nut or snap ring. If I remember correctly, my BW T10 with the small retainer uses a nut on the input shaft. The retainer is machined for that retainer nut. If the replacement retainer was from a transmission with a snap ring, it may not fit correctly or hold the front bearing in position properly.
If you notice in the picture I posted, you can see that the bolts are further inboard of the outer ring of the retainer on the B/W than your Muncie.
This is telling me that the Muncie has a larger front bearing than the B/W.
This is telling me that the Muncie has a larger front bearing than the B/W.
I just remembered that I got a front bearing retainer from Cajun John, several years ago, that fit my T10 and the larger truck bell housing. I'm thinking he told me it was from a Saginaw transmission, but I'm not 100% sure.
That is what this old 3 speed is.
What about using a spacer ring to make up the difference?
63409
Well Known Member
The Muncie does have a larger front bearing retainer which fits the 553 bell housing but the bolt pattern isn’t the same as my 63 Borg and Warner which has a smaller front bearing retainer and to small for the 553 bell housing.
First picture is the Borg and Warner which has 4 inches in diameter front bearing retainer and second picture below is the early 1964 Muncie with a diameter of 4 1/2 inches and the bolts don’t lineup with my Borg and Warner. Third picture is with the 553 bell housing and its diameter is 4 1/2 inches just like the Muncie but the Borg and Warner bearing retainer diameter is too small and the bolts don’t lineup with my Muncie front bearing retainer.
Bell housing with the correct hole 
A good machinist can make a spacer ring so you can just bolt in your transmission with no changes. This could be an option if the bell housing number is the same between the small and big hole.
A good machinist can make a spacer ring so you can just bolt in your transmission with no changes. This could be an option if the bell housing number is the same between the small and big hole.
You may be able to use 1/4" steel or aluminum square stock to make a spacer ring for the small retainer.