Posi Case Assembly
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
Posi Case Assembly
Eaton type from a '73 diff. in my '65 Anybody ever assemble the posi case without using the cage/preaload spring assembly? Also: I have the steel clutch pack with the "snowflake" discs between the plates. Should I scrap them and install "solid" steel clutches. They are in good shape with no discoloration or cracks. The posi works "good", but that's subjective. In other words, I always get 2 parallel black lines, not one.
Burning Brakes
Joined: Dec 2010
Posts: 1,224
Likes: 361
From: Southington CT
Eaton type from a '73 diff. in my '65 Anybody ever assemble the posi case without using the cage/preaload spring assembly? Also: I have the steel clutch pack with the "snowflake" discs between the plates. Should I scrap them and install "solid" steel clutches. They are in good shape with no discoloration or cracks. The posi works "good", but that's subjective. In other words, I always get 2 parallel black lines, not one.
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
Are you saying that I should replace the "snowflakes" with "solids" even though the snowflakes are in good condition? I have watched the online videos on setup without the cage and springs, but am reluctant to replace the clutch packs because of the "50 revolutions in both directions" to wear-in a new clutch pack pair. However, if it's important then I'll do it. Also, I hear that the "solids" are more prone to chattering/banging when making turns.
Last edited by 65tripleblack; Sep 13, 2015 at 08:51 AM.
Burning Brakes
Joined: Dec 2010
Posts: 1,224
Likes: 361
From: Southington CT
Located a brand new Eaton, late model series 3 case for under 300 dollars. Now will polish it to eliminate stress risers, and will chamfer the spider gear shaft holes as well.
Are you saying that I should replace the "snowflakes" with "solids" even though the snowflakes are in good condition? I have watched the online videos on setup without the cage and springs, but am reluctant to replace the clutch packs because of the "50 revolutions in both directions" to wear-in a new clutch pack pair. However, if it's important then I'll do it. Also, I hear that the "solids" are more prone to chattering/banging when making turns.
Are you saying that I should replace the "snowflakes" with "solids" even though the snowflakes are in good condition? I have watched the online videos on setup without the cage and springs, but am reluctant to replace the clutch packs because of the "50 revolutions in both directions" to wear-in a new clutch pack pair. However, if it's important then I'll do it. Also, I hear that the "solids" are more prone to chattering/banging when making turns.
Last edited by 4 Speed Dave; Sep 13, 2015 at 06:00 PM.
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
Le Mans Master
Joined: Nov 2003
Posts: 5,772
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
I replaced my 65 rear a 75 I picked up. I did the rebuilt the posi without using the cage and springs. Doing the 50 rotations on each side is a very vague process and shimming tghe side gears depends on solely on feel. I called one of the big diff outfits and talked to the owner about getting a turning torque measurement. He was pretty short with me and wasn't at all interested. The feel method is great when you do them all the time but for a one time deal it leaves allot to be desired. So I did the rebuild as best I could following the instructions. Diff was quiet and worked well. Took the car on the Power Tour and through Tail of the Dragon on the way home. If you have never been there its 318 turns in 11 miles. Needless to say the diff got a workout. I now have excessive play in the stub axles that was not there when I completed the overhaul. I suspect the posi clutches have "worn in" more and I have to take it apart and set it up again.
Just my experience. Hopefully you will have better luck.
Tom
Just my experience. Hopefully you will have better luck.
Tom
Le Mans Master
Joined: Apr 2002
Posts: 5,537
Likes: 280
From: Egg Harbor Township NJ
2015 C2 of Year
St. Jude Donor '04-'05-'06-'07-'08-'09-'10, '14-'15
Eaton type from a '73 diff. in my '65 Anybody ever assemble the posi case without using the cage/preaload spring assembly? Also: I have the steel clutch pack with the "snowflake" discs between the plates. Should I scrap them and install "solid" steel clutches. They are in good shape with no discoloration or cracks. The posi works "good", but that's subjective. In other words, I always get 2 parallel black lines, not one.
Joe give Mona A Call... She'll give you the real skinny...
Last edited by Viet Nam Vett; Sep 14, 2015 at 09:02 PM.
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
Joe give Mona A Call... She'll give you the real skinny...
https://www.youtube.com/watch?v=_ug9pP7dftM
https://www.youtube.com/watch?v=6qgREMBTE28
https://www.youtube.com/watch?v=_ug9pP7dftM
https://www.youtube.com/watch?v=6qgREMBTE28
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Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
Likes: 239
From: Ocean Township NJ
I replaced my 65 rear a 75 I picked up. I did the rebuilt the posi without using the cage and springs. Doing the 50 rotations on each side is a very vague process and shimming tghe side gears depends on solely on feel. I called one of the big diff outfits and talked to the owner about getting a turning torque measurement. He was pretty short with me and wasn't at all interested. The feel method is great when you do them all the time but for a one time deal it leaves allot to be desired. So I did the rebuild as best I could following the instructions. Diff was quiet and worked well. Took the car on the Power Tour and through Tail of the Dragon on the way home. If you have never been there its 318 turns in 11 miles. Needless to say the diff got a workout. I now have excessive play in the stub axles that was not there when I completed the overhaul. I suspect the posi clutches have "worn in" more and I have to take it apart and set it up again.
Just my experience. Hopefully you will have better luck.
Tom
Just my experience. Hopefully you will have better luck.
Tom
Did you turn 50 revs in both directions. According to Tom's video, he turned it 50 times both ways.............re-shimmed it and then turned it ANOTHER 50 times both ways, checked it again and finally set the end play of the stubs. Sounds like a huffer-puffer without the lathe.
Mine works so well that I'm in a conundrum as to whether to fix sompin' that ain't broken. Not sure yet what I'll do about the clutch pak.
Le Mans Master
Joined: Nov 2003
Posts: 5,772
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Sky,
Did you turn 50 revs in both directions. According to Tom's video, he turned it 50 times both ways.............re-shimmed it and then turned it ANOTHER 50 times both ways, checked it again and finally set the end play of the stubs. Sounds like a huffer-puffer without the lathe.
Mine works so well that I'm in a conundrum as to whether to fix sompin' that ain't broken. Not sure yet what I'll do about the clutch pak.
Did you turn 50 revs in both directions. According to Tom's video, he turned it 50 times both ways.............re-shimmed it and then turned it ANOTHER 50 times both ways, checked it again and finally set the end play of the stubs. Sounds like a huffer-puffer without the lathe.
Mine works so well that I'm in a conundrum as to whether to fix sompin' that ain't broken. Not sure yet what I'll do about the clutch pak.
I don't mean to turn you off from doing the rebuild just giving my experience. Truth be known I would would probably do it again IF I needed the diff rebuilt anyway. BUT I would find some way to complete the rotations with a machine. By hand was too rough on my old shoulders and I don't believe it gives the proper wear in of the clucth packs.
Tom
Last edited by Sky65; Sep 16, 2015 at 10:32 AM.
Thread Starter
Safety Car
Joined: May 2003
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From: Ocean Township NJ
Yes I turned it 50 times each way. Multiple times! I did it after each shim change. I don't have a lathe so I did it by hand. I have been suffering with shoulder pain ever since from tendinitis in both shoulders. That was eight months ago. The other problem with turning by hand is you don't get a continuous rotation. You start and stop a couple times to get one complete rotation. I don't know if that gives the same wear in as 50 continuous turns on a machine. I don't know for sure but I'm thinking not because mine is not too loose. I haven't pulled ot apart yet. I replaced my old diff do to excessive stub axle wear. While I was doing it I thought why not "Tune " it. I don't think I would take apart a perfectly fine working diff to Tune it.
I don't mean to turn you off from doing the rebuild just giving my experience. Truth be known I would would probably do it again IF I needed the diff rebuilt anyway. BUT I would find some way to complete the rotations with a machine. By hand was too rough on my old shoulders and I don't believe it gives the proper wear in of the clucth packs.
Tom
I don't mean to turn you off from doing the rebuild just giving my experience. Truth be known I would would probably do it again IF I needed the diff rebuilt anyway. BUT I would find some way to complete the rotations with a machine. By hand was too rough on my old shoulders and I don't believe it gives the proper wear in of the clucth packs.
Tom
I see no reason why I can't remove the preload springs and cage, shim the side gears per Tom's video, and not turn the case since my clutches have long ago worn-in.
Burning Brakes
Joined: Dec 2010
Posts: 1,224
Likes: 361
From: Southington CT
Thanks for the input. It has caused me to re-think this. Since the clutch paks are in good condition (although they are not solid discs) and the posi works as it should, as well as the fact that I'm not running wide tires or drag radials, I'll tune the posi without replacing the clutches.
I see no reason why I can't remove the preload springs and cage, shim the side gears per Tom's video, and not turn the case since my clutches have long ago worn-in.
I see no reason why I can't remove the preload springs and cage, shim the side gears per Tom's video, and not turn the case since my clutches have long ago worn-in.
Melting Slicks
Joined: Feb 2004
Posts: 2,040
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From: State of Confusion!!!
2018 C2 of Year Winner
That picture is EXACTLY why I sent mine to a former member of this forum who resides in the New Haven area. It was behind a ZZ454 and a Tremec TKO 600 which took a pretty good deal of abuse with no signs of getting tired.
The car has been sold, but still trouble free as far as I know. Do it right the first time and avoid the labor of dropping it out to do it again!!!
If you would like contact info, shoot me a PM.
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
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From: Ocean Township NJ
And you didn't have problems like Sky65? Read his posts 6 and 10.
I'm confident in my ability, but don't want to have to worry about the clutch pack clearance loosening over time without the preload spring assembly.
Remember that I run a high horsepower 327 without monster torque. I also run 215/70 R 15 radials at the strip. No drag radials, no slicks.
Last edited by 65tripleblack; Sep 16, 2015 at 02:54 PM.
Thread Starter
Safety Car
Joined: May 2003
Posts: 4,797
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From: Ocean Township NJ
OUCH!!!!!
That picture is EXACTLY why I sent mine to a former member of this forum who resides in the New Haven area. It was behind a ZZ454 and a Tremec TKO 600 which took a pretty good deal of abuse with no signs of getting tired.
The car has been sold, but still trouble free as far as I know. Do it right the first time and avoid the labor of dropping it out to do it again!!!
If you would like contact info, shoot me a PM.
That picture is EXACTLY why I sent mine to a former member of this forum who resides in the New Haven area. It was behind a ZZ454 and a Tremec TKO 600 which took a pretty good deal of abuse with no signs of getting tired.
The car has been sold, but still trouble free as far as I know. Do it right the first time and avoid the labor of dropping it out to do it again!!!
If you would like contact info, shoot me a PM.
He's booked until March/April 2016.