Hey guys,

Some months ago I posted pics of my diff bracket that I created to allow me to bolt up a C5 diff in my 2005 C6. We all know how weak the diffs are in the 2005 C6 and when I broke mines I couldn't afford to buy a C6 diff and pay to get it built. So I created a bracket to allow me to use a C5 diff which is stronger and cheaper. It was an aluminum bracket made of 6061 T6 that worked great but unfortunetly the CNC machine I was using to make the brackets has been out of service for a few months and a buddy of mine had just blown his diff in his C6 3 wks ago. So I had to help him. With no CNC machine I decided to make one again out of steel just like the first bracket I made, only stronger and better.

What I came up with was a simple yet very strong design. I didn't think about taking any pics of the bracket once installed but I did remember to take a few pics of the 2nd bracket I just made.

Here it is...


Here is a pic of the bracket that's welded to the cradle.....



I've also created a bracket that REQUIRES NO WELDING AT ALL!!!! It's a complete bolt-on application which uses this bracket as well. I just have a little more welding to do to it and it's finished. I'll post pics of it once it's painted and if I can find another C6 locally i'll take pics of it installed.

Engoy...

UPDATE!!!!!

Ok guys here is the "bolt-on" version of the bracket. Since I couldn't find a local candidate to try out the new bracket and all my buddies already have the "weldon" version, I had to try it myself. So I ripped out my welded base plate and installed this unit. Here are a few pics...



Here is the lower bracket bolted to the cradle. The only modification to the cradle is drilling 4 holes. Everything else bolts right up.

Here is a pic of the bottom of the cradle with the bracket bolted up.

And here is the upper and lower bracket installed on my car.


Enjoy...

 

Are there other parts needed to bolt up the C5 diff to our 2005s? Or just this bracket? I'm surprised no one has marketed and sold these brackets for us 2005 guys! I will start to keep my eyes open for C5 Z diff, because I am worried about mine.

 

Contemplating this myself. Do both the C5 and C5Z diffs need an adapter to fit into the C5s?

 

If you're using the "weld" on version then the only other thing you'll need to do is weld a base plate to the C6 cradle which I have done in all the installs. The "Bolton" version will require no base plate to be welded because it uses a "bolton" style base. I personally like the weldon version because of the cleaner install. Other than this...no other parts are needed to bolt up the C5 diff to a 05 C6.

If you need a C5Z diff, let me know. We pick them up from Corvette wrecking yards nearby when they have them in stock. I just found one the other day for $650.

I think you meant to ask if the C5 or the C5Z diff will bolt up to the C6. Both C5 or C5Z diffs will require this bracket to work. The diffs themselves bolt up to the tranny with no problem. This bracket bolts the diff to the cradle.

Just a side note...all 3-rib C5 diffs are pretty much the same in strength. From what I've seen the ZO6 diffs have treated gears and a few other upgrades but the cases themselves are the same in strength. If i'm wrong let me know.

 

Very cool conversion.

Are the C5 diffs also stronger than the 2006 and up diffs?

 

You'll get different opinions, but it is generally believed that the 06+ is a stronger design than the C5. The main advantage to using a C5 diff is that it is stronger than the 05 diff and significantly cheaper and more plentiful than the 06 and up design. For many, the C5 design is plenty strong enough. I managed to find a low mileage 06+ diff for mine for $750, so that's the route I went.

 

Some believe the C5 are just as strong and others believe the 06+ diff are stronger. I think the side cases of the 06+ are stronger than the C5s. IMO these diffs can take a hell of a beating. There is no such thing as a bulletproof diff. They all have their limits and wheel hop is the #1 killer. I've seen so many 9 second C5s cutting 1.3-1.4 60ft times with no problem. Of course they're built but the case is pretty much stock.

06+ diffs are pricer than the C5s and are a good route but you still have to buy the adapter which is another $400. I didn't want to spend that much so I just bought a used 3-rib C5 diff for $550 from a salvage yard and made my bracket. My diff went thru about 120 passes on slicks and never had a problem. It's now built with 3.90s and ZO6 output shafts. Needless to say...I don't plan on upgrading it anytime soon.

 

Way to go Sparo! That new bracket looks great.

I've got 133 passes and 1.5 years on my c5 diff. It's holding up great and if it blows it's much cheaper to replace.

 

Joe you and you're car aren the exception to every rule anyway....you're probably still running the stock original clutch even though your now into the 10s.

 

Yes sir!! 433 runs and 51xxx daily driving miles. Original equipment clutch. Took it up to Barrett Jackson Friday, still gets the looks even in that atmosphere.

It's a great car. The key I think is never pop the clutch, get out upon any hint of wheel hop, and keep your clutch fluid clean.

 

There are many more c5 diffs that have been run through the ringer with high powered drag racers than 06 and up c6 diffs. I'm not saying the c5s are stronger but there is much more empirical data available to at least have an idea of what you can and can't get away with.

The first mod I did on my 2005 back in 2006 was to have Cartek put a c5 z06 diff in it. I'm happy I did the mod.

 

Thanks Joe. Glad to see you made it in the 10s. I bet you were happy when you saw that timeslip. Can't believe the stock clutch survived that long. Lol. Good job man.

 

Thanks. I actually hurt my voice yelling when they gave me the slip.

Check out the vids and turn of events. My buddy blew his engine last summer and we agreed he would build it so we would be competitive....he got his 10 on the run 15 minutes before me.

Check it out.

http://forums.corvetteforum.com/c6-t...e-victory.html

 

Man you were flying on that 10.995 pass. 2nd gear almost sounded like your clutch was slipping but you can hear the tires trying to hold grip. Man I can't wait to go out to the track again. I just have so much work right now and when work permits, it rains.

 

I should have pics of the "bolt-on" version in a few days guys. I ran out of wire for my welder so it's holding me back.

 

Great! I'm going to the track this weekend so I may be in touch.

 

Bill would you get this done already??! Remember you can sell your 3:42 to an automatic guy as a nice upgrade for their car.....if you do it before it ends up like this!

 

Man, does that picture bring back memories.

 

Heres one for you. I have an 02 Z06 and I had the diff built...now I want to put that diff into my 05 XLR since nobody thinks its worth anything when you try to sell plus the gearing is just way better since the XKR is an auto.
Would this be my ticket?

 

Probably not but you can send the diff my way.

Just kidding. Sounds interesting.

Jeff