Half shaft questions
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Half shaft questions
Good morning everyone, I recently took my car to the track and snapped my left differential output shaft when launching the car. When I found out what it was I started doing research to figure out what to do to upgrade that part. I then came upon this thread
https://www.corvetteforum.com/forums...and-right.html
It made all the sense in the world so I went ahead and ordered the parts listed to upgrade my differential. I should’ve read a little bit more because now I am finding conflicting info as it seems some say that the C5Z axles are stronger than the ones I just ordered so I’m a bit confused. I’m wondering if the article is a little bit out of date now. Now I am also finding info that the later C6Z ones are in fact stronger so I’m just curious If anyone has done this lately and what type of results did they see. I’m also hoping that exact these parts will still fit because I know they did some design changes on the later C6z differentials. Any info you have is appreciated !!
https://www.corvetteforum.com/forums...and-right.html
It made all the sense in the world so I went ahead and ordered the parts listed to upgrade my differential. I should’ve read a little bit more because now I am finding conflicting info as it seems some say that the C5Z axles are stronger than the ones I just ordered so I’m a bit confused. I’m wondering if the article is a little bit out of date now. Now I am also finding info that the later C6Z ones are in fact stronger so I’m just curious If anyone has done this lately and what type of results did they see. I’m also hoping that exact these parts will still fit because I know they did some design changes on the later C6z differentials. Any info you have is appreciated !!
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You need to order all the parts for the C6 ZO6 differential. THEY ARE: Two output shafts, the splined gear for the shaft, the limited slip clutches, both belleview springs and all the seals (left and right output shaft seals and left and right case O rings).
The C6 ZO6 parts are much better designed and stronger than any of the old C5 parts.
I have done this up-grade and its wonderful and can be bone by the DYI person. NO alignment or differential set up is changed. I also up-graded the spider gear cross shaft but I have NOT seen any one selling the improved cross shaft in a while.
Give me an e-mail and I will send you more info on this project..
Bill
The C6 ZO6 parts are much better designed and stronger than any of the old C5 parts.
I have done this up-grade and its wonderful and can be bone by the DYI person. NO alignment or differential set up is changed. I also up-graded the spider gear cross shaft but I have NOT seen any one selling the improved cross shaft in a while.
Give me an e-mail and I will send you more info on this project..
Bill
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Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The FORUM no longer give you the ability to copy and paste in something in your post.. At least I have NOT figured out how to do it....! Give me an e-mail address and I will send you LOADS of stuff.. I gave you my number. Give me a call and we can shoot the breeze on this topic..
Melting Slicks
Joined: Nov 2017
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I did a lot of research before having my diff regeared with 4.10s and decided to only swap the left output shaft. That's the long one in the picture and most common to break. They did replace the bellevue springs as well, it's extremely common for the factory ones to already be broken when the case is opened. If you really think you'll abuse it, go ahead and upgrade everything, but for a street car that will maybe see the drag strip a couple times, just replacing the weak link (left output shaft) should be sufficient.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The short shaft is also weak and has a concaved area in the gear part of the shaft that commonly snaps due to not enough structure between the gear portion of the part and the shaft portion of the part. The C6 part is a machined shaft and the gear portion fits onto a spline on the shaft and is C pinned together.
BC
BC
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Bill and others, thank you for the help! I ordered the parts described in the link I pasted in my original post exactly. I also got the right side shaft, the issue is that the gear is on back order. I’m going to try to find it somewhere else. I want to launch the car pretty hard and have a hope that it holds together. When i broke this the car just got hit with a 150 shot on a non progressive controller 😳.
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Burning Brakes
Joined: Jul 2005
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From: Cedar Rapids IA
Some good advice in this thread: https://www.corvetteforum.com/forums...-upgrades.html
Specifically post #6.
Specifically post #6.
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well i already have the parts on the way, so I am going to go with the C6Z stuff. I have heard stories like his, but i have also heard that folks diffs have survived fairly well after upgrading the parts that i am upgrading. I do agree that it's in the launch, and what i need to practice so i don't break the next thing like he states.
Melting Slicks
Joined: Nov 2017
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FWIW I have 305/35/18 Toyo R888s in the rear with Bilstein B8 shocks and so far, I have experienced zero wheel hop launching on the street. The R888's are sticky as it is, but a drag radial (especially on a prepped track surface) will cause even more drivetrain shock. The Bilsteins do a great job preventing wheel hop and I'm not the only one to notice this. I've never launched higher than about 3k rpm on the street as well. Not worth even risking it. The right tire, suspension, and surface (and knowing what NOT to do) are all key 
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I may have to try the bilsteins....thanks for the info. I know that i never had much wheel hop on the street either though. its obviously a completely different animal than a prepped track. I think its more about me learning to launch the damn thing hard but still slipping enough to not hop. Oh well, Ill get it back together and go practice some more!! I already have the diff out, just waiting for parts.