Busted rear end
Thread Starter
Intermediate
Joined: May 2008
Posts: 35
Likes: 0
From: California
Busted rear end
Ok I really need help just so I can stop stressing..LOL. Have a 05 M6 Z51 with 60k. A couple of months ago the stock clutch went out. I have a spec II clutch installed.....tonight I was getting on the car alittle.......Tried to launch from 1st gear @3000 rpm, heard a pop, the top of the housing blown out..fluid everywhere...........my question what could I be looking at in getting this repaired
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
Here is an option that is available. The c5 rear is about $1500 or so without a core, a 06+ C6 rear is about $2500 without a core. You have to build a bracket for the C5 rear, or buy a new rear trans mount for the C6.
http://forums.corvetteforum.com/c6-t...-write-up.html
http://forums.corvetteforum.com/c6-t...-write-up.html
Race Director
Joined: Jan 2006
Posts: 18,396
Likes: 169
I've been whinning about the 2005's differential cases for 4 years. It is the case, not the internals, that is weak. Just like the idiots at GM to build an engine with 50 more horsepower and torque, then save $5 in aluminum by designing a thin-walled case. I wish someone would build a class action against GM and make them retrofit all manual 2005's with the better case offered in the later models.
And, GM knew they had a problem, because they attempted a fix by using the computer's software. Remember torque management? That was a big arguement back in 2005, where GM programed the PCM to reduce the power levels in 1st and 2nd gears in an attempt to protect the car's differential cases. I, too, have a 2005, mn6, and it scares me that someday I will have the case grenade, and take the tranny with it. That's about an $8k repair bill.
And, GM knew they had a problem, because they attempted a fix by using the computer's software. Remember torque management? That was a big arguement back in 2005, where GM programed the PCM to reduce the power levels in 1st and 2nd gears in an attempt to protect the car's differential cases. I, too, have a 2005, mn6, and it scares me that someday I will have the case grenade, and take the tranny with it. That's about an $8k repair bill.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
If you are personally interested, the Pfadt C5 mount with a smaller center bracket, combined with a plate to sandwich the center of the C6 cradle, would be easy to make and as you noted well received. Welding would be required to the plate, or perhaps you could even do a bolt in to sandwich the cradle - that would really be a DIY at home project.
Here's a couple of pics of how it would work. This is an existing Pfadt c5 mount.
Cartek made me this mount:
Here's the Pfadt.
Here's the plate you weld to the c6 cradle.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
I've been whinning about the 2005's differential cases for 4 years. It is the case, not the internals, that is weak. Just like the idiots at GM to build an engine with 50 more horsepower and torque, then save $5 in aluminum by designing a thin-walled case. I wish someone would build a class action against GM and make them retrofit all manual 2005's with the better case offered in the later models.
And, GM knew they had a problem, because they attempted a fix by using the computer's software. Remember torque management? That was a big arguement back in 2005, where GM programed the PCM to reduce the power levels in 1st and 2nd gears in an attempt to protect the car's differential cases. I, too, have a 2005, mn6, and it scares me that someday I will have the case grenade, and take the tranny with it. That's about an $8k repair bill.
And, GM knew they had a problem, because they attempted a fix by using the computer's software. Remember torque management? That was a big arguement back in 2005, where GM programed the PCM to reduce the power levels in 1st and 2nd gears in an attempt to protect the car's differential cases. I, too, have a 2005, mn6, and it scares me that someday I will have the case grenade, and take the tranny with it. That's about an $8k repair bill.
The c5 diff is about 1/2 the price of a c6 diff so that's why I went with it.
Here's what the rear end looks like when it goes. This is a common picture at my shop Horsepower Sales. Palm Beach Int'l Raceway claims many 05 rears.
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
Yea, I've seen those pics Joe. Those and Sparo2's instructions and pictures help out a lot. 
I know Cartek does the conversions but I'm not sure if they sell it or just do the conversions in house. Seems like that bracket they made for you and a pre-cut plate to weld into the cradle would be all that is required. Granted if you did not have welding capabilities you'd have to take the cradle and plate to a shop to have it done but it's still better than the alternative IMO (being shelling out much more $ to convert to a '06+ C6 diff).
I know Cartek does the conversions but I'm not sure if they sell it or just do the conversions in house. Seems like that bracket they made for you and a pre-cut plate to weld into the cradle would be all that is required. Granted if you did not have welding capabilities you'd have to take the cradle and plate to a shop to have it done but it's still better than the alternative IMO (being shelling out much more $ to convert to a '06+ C6 diff).
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Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
NM, I see now that the mount they made for you is to try and utilize the PFADT C5 mount. That would be nice but it seems like its going through a lot to try and integrate the PFADT mount. I would rather just see a bracket/mount that bolts to the bottom of the C5 diff that would bolt to the plate welded into the C6 cradle.
Tech Contributor
Joined: Jul 2002
Posts: 14,949
Likes: 263
From: St. Louis, MO
St. Jude Donor '08
NM, I see now that the mount they made for you is to try and utilize the PFADT C5 mount. That would be nice but it seems like its going through a lot to try and integrate the PFADT mount. I would rather just see a bracket/mount that bolts to the bottom of the C5 diff that would bolt to the plate welded into the C6 cradle.
Cartek made my mount for me, but Sparo said he had trouble getting one so he just made his own.
Burning Brakes
Joined: Jun 2008
Posts: 1,214
Likes: 3
From: CA
I actually made a few diff mounts for a few people now. I haven't heard of any failing. It's not really difficult to someone that's good at fabricating. I enjoy it and have all the tools necessary to make these mounts so it's easy for me.
I guess now that my entire driveline is out of the car I can maybe come up with a bolt-in kit if I had someone interested.
I guess now that my entire driveline is out of the car I can maybe come up with a bolt-in kit if I had someone interested.
Drifting
Joined: Apr 2005
Posts: 1,366
Likes: 9
From: Jacksonville FL
Sorry to hear that! 
But welcome to the club! I blew mine out at the strip with a 1200 RPM clutch drop (damn near idle). The secret to launching a stock C6 is to roll into the throttle in first otherwise you run the risk of wheel hop and blowing your rear end again. The 06 and up C6 rears are much stronger than the 05's, and I believe the C5 rear is stronger than the C6. Although I am sure that someone will correct me on this if I am incorrect. Good luck and let us know what you end up doing. Pics of the repair too please!
But welcome to the club! I blew mine out at the strip with a 1200 RPM clutch drop (damn near idle). The secret to launching a stock C6 is to roll into the throttle in first otherwise you run the risk of wheel hop and blowing your rear end again. The 06 and up C6 rears are much stronger than the 05's, and I believe the C5 rear is stronger than the C6. Although I am sure that someone will correct me on this if I am incorrect. Good luck and let us know what you end up doing. Pics of the repair too please!
