C3 rear differential
Thread Starter
2nd Gear
Joined: Sep 2022
Posts: 2
Likes: 0
C3 rear differential
Hi all, I'm new to this forum thing. I am looking for some help with my 76 c3 rear differential. Seem the driver side wheel half shaft has movement from top to bottom. Is this normal?
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Moved to C3 Tech for assistance.
Race Director
Joined: Jul 2015
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From: SW Florida.
is the movement at the diff? at the outer wheel bearing? or in the u-joint? either way GTR1999 will weigh in soon. if it is the diff, send it to him. he may also do the trailing arms (outer wheel bearings, bushings, etc) but not sure.
Race Director
Joined: Mar 2016
Posts: 14,289
Likes: 8,091
From: Napa Valley California
GTR1999 (Gary Ramadei) is the most knowledgeable person to ask questions regarding the rear differential.
You can send him a PM and ask him directly.
He is also the ONLY person I would trust working on my differential.
You can send him a PM and ask him directly.
He is also the ONLY person I would trust working on my differential.
Le Mans Master
Joined: Jun 2019
Posts: 7,641
Likes: 2,461
From: Indiana
Op
take a look here for end play..and other advice i got that may help you.
also buy a factory shop manual.
https://www.corvetteforum.com/forums...ay-advice.html
wheel bearing you need to disconnect half shaft then measure bearing movement.
welcome to forum..
take a look here for end play..and other advice i got that may help you.
also buy a factory shop manual.
https://www.corvetteforum.com/forums...ay-advice.html
wheel bearing you need to disconnect half shaft then measure bearing movement.
welcome to forum..
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Tech Contributor
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From: Connecticut, USA
I'm assuming you are referring to the axle endplay in the differential which can be transferred to the wheel easily. If you have movement at 6 & 12 have someone move the wheel while you watch it to see if the 1/2 shaft is pulling out the axle. If there is play at 3& 9 check the rear bearings.
If your 76 diff is original and has over 45k miles you will need axles most likely. If the diff was ever worked on in the past you may need axles, a good posi tune, or complete rebuild- all depending on how competent the previous workers were. Many are not that good with these cars, even if they are an otherwise good general mechanic. The best of the lot will go by the manual but lack the knowledge of what to look for with these specific differentials. '76 for instance had poor axles, ring gear bolts, and clutches. If there is play from the axle moving, you need to check to see if the axle ground into the side bore. possibly wrecking the whole diff. That should be obvious and most likely would have a good oil leak at that point.
Thread Starter
2nd Gear
Joined: Sep 2022
Posts: 2
Likes: 0
The 1/2 shaft does indeed need to move up and down, the axle in the differential should not move in or out more than 010" Huge difference between what a part should do and not do.
I'm assuming you are referring to the axle endplay in the differential which can be transferred to the wheel easily. If you have movement at 6 & 12 have someone move the wheel while you watch it to see if the 1/2 shaft is pulling out the axle. If there is play at 3& 9 check the rear bearings.
If your 76 diff is original and has over 45k miles you will need axles most likely. If the diff was ever worked on in the past you may need axles, a good posi tune, or complete rebuild- all depending on how competent the previous workers were. Many are not that good with these cars, even if they are an otherwise good general mechanic. The best of the lot will go by the manual but lack the knowledge of what to look for with these specific differentials. '76 for instance had poor axles, ring gear bolts, and clutches. If there is play from the axle moving, you need to check to see if the axle ground into the side bore. possibly wrecking the whole diff. That should be obvious and most likely would have a good oil leak at that point.
I'm assuming you are referring to the axle endplay in the differential which can be transferred to the wheel easily. If you have movement at 6 & 12 have someone move the wheel while you watch it to see if the 1/2 shaft is pulling out the axle. If there is play at 3& 9 check the rear bearings.
If your 76 diff is original and has over 45k miles you will need axles most likely. If the diff was ever worked on in the past you may need axles, a good posi tune, or complete rebuild- all depending on how competent the previous workers were. Many are not that good with these cars, even if they are an otherwise good general mechanic. The best of the lot will go by the manual but lack the knowledge of what to look for with these specific differentials. '76 for instance had poor axles, ring gear bolts, and clutches. If there is play from the axle moving, you need to check to see if the axle ground into the side bore. possibly wrecking the whole diff. That should be obvious and most likely would have a good oil leak at that point.