Would "You" attempt it ?
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Would "You" attempt it ?
Just for fun. 
Would you attempt to replace 4th gear brass blocker synch ring without removing the trans from the car ? Can it be done ?
Years ago I had a Muncie come in that had some clash going into high gear. The guy had already been to several shops and had estimates for R&R and overhaul but no one had actually removed the side cover and looked inside.
I removed the cover and discovered 4th blocker was cracked .
I laid back on my creeper and looked for a bit and I think I might have been able to sneak in a new ring by injecting grease into the bearing assembly inside the input shaft and splitting the trans and sliding the rear back to gain enough clearance between the input shaft and 4-3 synchro.
I think the reverse idler gears might have given me fits.
Of course it wouldn't have made good business sense to do this because the tranny had "never" been rebuilt and I would have been screwing myself money wise only to see if it could be done.
What do you guys think ,could it be done or when thinking about it,(i didn't think long) did I miss an important point ?
Would you attempt to replace 4th gear brass blocker synch ring without removing the trans from the car ? Can it be done ?
Years ago I had a Muncie come in that had some clash going into high gear. The guy had already been to several shops and had estimates for R&R and overhaul but no one had actually removed the side cover and looked inside.
I removed the cover and discovered 4th blocker was cracked .
I laid back on my creeper and looked for a bit and I think I might have been able to sneak in a new ring by injecting grease into the bearing assembly inside the input shaft and splitting the trans and sliding the rear back to gain enough clearance between the input shaft and 4-3 synchro.
I think the reverse idler gears might have given me fits.
Of course it wouldn't have made good business sense to do this because the tranny had "never" been rebuilt and I would have been screwing myself money wise only to see if it could be done.
What do you guys think ,could it be done or when thinking about it,(i didn't think long) did I miss an important point ?
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
Melting Slicks
Joined: Jan 2012
Posts: 3,039
Likes: 504
From: myrtle beach sc
Army
I have a GM replacement frame on my 68 and the removable transmission crossmember (that came on all of the replacement frames) is just wonderful to have, when working on the trans. Lou.
Le Mans Master
Joined: Aug 2001
Posts: 7,804
Likes: 4
From: Standing still with all my might Texas
Cruise-In X Veteran
St. Jude Donor '09-'11
Just for fun.
Would you attempt to replace 4th gear brass blocker synch ring without removing the trans from the car ? Can it be done ?
Years ago I had a Muncie come in that had some clash going into high gear. The guy had already been to several shops and had estimates for R&R and overhaul but no one had actually removed the side cover and looked inside.
I removed the cover and discovered 4th blocker was cracked .
I laid back on my creeper and looked for a bit and I think I might have been able to sneak in a new ring by injecting grease into the bearing assembly inside the input shaft and splitting the trans and sliding the rear back to gain enough clearance between the input shaft and 4-3 synchro.
I think the reverse idler gears might have given me fits.
Of course it wouldn't have made good business sense to do this because the tranny had "never" been rebuilt and I would have been screwing myself money wise only to see if it could be done.
What do you guys think ,could it be done or when thinking about it,(i didn't think long) did I miss an important point ?
Would you attempt to replace 4th gear brass blocker synch ring without removing the trans from the car ? Can it be done ?
Years ago I had a Muncie come in that had some clash going into high gear. The guy had already been to several shops and had estimates for R&R and overhaul but no one had actually removed the side cover and looked inside.
I removed the cover and discovered 4th blocker was cracked .
I laid back on my creeper and looked for a bit and I think I might have been able to sneak in a new ring by injecting grease into the bearing assembly inside the input shaft and splitting the trans and sliding the rear back to gain enough clearance between the input shaft and 4-3 synchro.
I think the reverse idler gears might have given me fits.
Of course it wouldn't have made good business sense to do this because the tranny had "never" been rebuilt and I would have been screwing myself money wise only to see if it could be done.
What do you guys think ,could it be done or when thinking about it,(i didn't think long) did I miss an important point ?
Murphy's law would probably also cause one or both gaskets to tear when you pull the tail housing and mid plate, which means you would have to pull it anyway to replace them.
Limping across the line
Joined: Oct 2002
Posts: 5,299
Likes: 109
From: Peoria Az
First problem will be sliding tail housing off. Doubt there is enough room. 2. Spedo drive gear is pressed on pretty good.
3. once you pull mid plate trying to keep mainshaft in place will be difficult to say th eleast.
4. Working on your back is going to Suck
3. once you pull mid plate trying to keep mainshaft in place will be difficult to say th eleast.
4. Working on your back is going to Suck
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 282
From: Dyersburg TN
pull it
such a easy job compared to an automatic. My 67 Chevelle ate clutches so much I got really good at it dropping the tranny. I burnt a clutch on way home from work, swapped in new disk and still made my date that night. Of course I was 20 years old at the time 
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Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
Think we've all learned this lesson more than once. Always turns out to be a much better job, just pulling the whole unit. Chances are, you'll be needing to do more work than you first thought on the tranny anyway.
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Drop the tranny, you can pull it on your back on jackstands easy. I actually did my TKO 600 ( f'ing heavy) that way but I believe I would pull my arms out of their sockets if I tried to that today.
Thread Starter
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
(I'm not really going to attempt it,I'm just really board,all our stuff is all packed up to move south,were waiting on the bank to close the sale on my house.
)
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Back when I was doing transmissions at the dealer, if the torque convertor didn't need anything I was rebuilding the 125/125C (front wheel drive 3 speed auto) without pulling them out. Changed the final drive assembly on one car 4 times in one day to satisfy the service manager. (noise issue that wasn't there to start with, but the customer had convinced him it howled like a siren). No real deal. Tried it one time on a 440-T4 (same plan, but 4 speed auto), KEY WORD--"one time".
Some of the stuff looks like it might be able to get done, but some things are better off doing the "hard" way. When the mainshaft comes off the input, the bearings are going to go everywhere. It would be tough to pump any grease into them to hold them, and then the be certain they stayed put when it went back in.
Some of the stuff looks like it might be able to get done, but some things are better off doing the "hard" way. When the mainshaft comes off the input, the bearings are going to go everywhere. It would be tough to pump any grease into them to hold them, and then the be certain they stayed put when it went back in.