Topic: 4 speed tailpiece seal
in Forum: C3 Driveline Components
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While I was at it, see below, I saw some leakage which I think is from the rear seal on the 4 speed so I'm shopping for a replacement (NAPA doesn't have them by the way!) I see kits offered that also include a bearing. Do I need to replace the bearing at the same time and can it be done with the tranny in the car without pulling the tailpiece off, or am I asking for more spanking! LOL.
So far as a result of my peeking under the rear of my car and thinking "that can use a little sprucing up" I have:
- Had the rear trailing arms rebuilt ($$$!!!)
- Rebuilt calipers with O rings - (painted red so I can pretend I have Wilwood brakes!)
- Replaced sway bar linkage and bushings
- replaced shocks
- installed adjustable strut rods (thanks John)
- replaced drive shaft u joints with Spicer's
- dropped diff and replaced seals and rear cover and bushings (thanks Jeffm)
- replaced diff cross member and bushings added Van Steel and Dragvette reinforcements (thanks Larry)
- Half shafts were good but added "french nuts" (thanks Joe)
- rebuilt rear spring with liners
- cleaned and rust proofed all of the frame I could get to
- replaced gas tank straps and hoses
- replaced rear tail light housings and fixed rear wiring harness "repairs (thanks Bubba!)
Why oh why can't I just keep my hands off! So many have helped on this forum (Joel, John, ebo, Jeffm, Larry, Joe - lot's of "J" first names now that I think about it!) I'm sure I'm missing many of you. Thanks to ALL of you for your help so far....especially Joel!
Someday I'll actually drive this thing but won't have any money left for gas!
Mario
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Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20218
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
The rear trans seal on the 4 speed should be the same as a 400 automatic, if it has the large yoke. If it has the small yoke, it's the same seal as the 350/700 trans. Since it's a '72, Imma assuming it still has the Muncie...so it should use the same seal as a 350. The BW ST10(and some Muncies) uses the larger, 400 trans seal.
|UPDATED|7/11/2013 10:09:56 AM (AZT)|/UPDATED|
No "bearing" back there...just a bushing. If the bushing is worn/bad, the only way to replace it is to remove the trans....

I'd say get the driveshaft loose, pull the yoke out, and see if it is worn. If it's smooth, and only has some minor wear, just replace the seal. If, however, the yoke has an area of obvious wear...and it will be obvious, then you'll need to replace both the yoke and the bushing, as well as the seal. Hopefully, the yoke is ok...those things are really, REALLY expensive...
|UPDATED|7/11/2013 10:09:56 AM (AZT)|/UPDATED|
Joel Adams
C3VR Lifetime Member #56
My Link
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Adams' Apple said: The rear trans seal on the 4 speed should be the same as a 400 automatic, if it has the large yoke. If it has the small yoke, it's the same seal as the 350/700 trans. Since it's a '72, Imma assuming it still has the Muncie...so it should use the same seal as a 350. The BW ST10(and some Muncies) uses the larger, 400 trans seal.
No "bearing" back there...just a bushing. If the bushing is worn/bad, the only way to replace it is to remove the trans....

I'd say get the driveshaft loose, pull the yoke out, and see if it is worn. If it's smooth, and only has some minor wear, just replace the seal. If, however, the yoke has an area of obvious wear...and it will be obvious, then you'll need to replace both the yoke and the bushing, as well as the seal. Hopefully, the yoke is ok...those things are really, REALLY expensive...
OOPs your right Adam I meant "bushing" and it is a Muncie. I was able to get the seal from Rock Auto and here is a pic of the yoke. It looks scratched in the picture but it is smooth to the touch, I can't feel any indentations when I run my fingernail over the yoke so I assume it's OK?

Mario

Moderator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20218
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Looks really nice in that pic! I'd say run some emory cloth(or sandpaper) over it, and run it! 

Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
in Forum: C3 Driveline Components
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