Difference between a C6 M6 diff and Z06 M6 rear diff?
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
C6 z diff is substantially stronger than a C6 manual diff. Stronger case, larger ring gear, stronger output shaft (not half shaft) design, set up for a diff cooler which is needed on the road course, 30 spline pinion gear.
C6z diffs are hard to break.
You cannot interchange them unless you change the transmission main shaft to correspond.
The c6Z diff will interchange with the A6 transmission and is a nice upgrade for that 2.56 or 3.15 diff for drag strip use.
C6z diffs are hard to break.
You cannot interchange them unless you change the transmission main shaft to correspond.
The c6Z diff will interchange with the A6 transmission and is a nice upgrade for that 2.56 or 3.15 diff for drag strip use.
Thread Starter
Burning Brakes
Joined: Dec 2008
Posts: 1,068
Likes: 1
From: Tuscaloosa Alabama
So to be clear:
You cannot interchange them unless you change the transmission main shaft to correspond
Ok, if I had the interchange components, would the gearing ratio be of advantage over the C6 base M6 diff? I assume it would as well as the strength factor..? Or are u suggesting it requires trans change?
I "assume" I have a 3:42..? C6 M6 in 06' LS2 car.
You cannot interchange them unless you change the transmission main shaft to correspond
Ok, if I had the interchange components, would the gearing ratio be of advantage over the C6 base M6 diff? I assume it would as well as the strength factor..? Or are u suggesting it requires trans change?
I "assume" I have a 3:42..? C6 M6 in 06' LS2 car.
Race Director
Joined: Oct 1999
Posts: 13,298
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From: Somers NY
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Me? Naa....
Actually, the hardest of hard core drag racers I know all swap OUT the C6z diff for a c6 diff, so that they can run 4:10 gears which is the hot ticket for drag racing!
You cannot get lower gears for the c6z and on the drag strip 4:10's rule the day.
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Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
Great to have for track use. I have a diff temp gauge on my car and it gets up to 250+ on the highway and I saw 270 when on the road course. The diff temp is what brought me into the pits, my factory z51 trans cooler and oil coolers were doing their jobs, temps of around 230 on each IIRC.
The Grand Sport manual has IMHO the best transmission of the bunch, it has the C5Z ratios in 1-3, and that 2.97 first is great for drag strip use (as I've proven over and over again). Fast guys are putting the grand sport ratios in their Z06 6060 transmisisons, it is the equivalent of putting in a 3.90 rear end.
Of course I think the best plan is to use the Z51 or GS transmission ratios and a set of 4.10 gears!
Can't get them for the larger Z/GS ring gear though.
Race Director
Joined: Aug 2005
Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
I found that you can have a standard diff with the same cooler as the Z06. The Z51's that got shipped to Europe have diff coolers. I am building a diff, using the European Z51 side cover, 3:73 gears, cut for he cooler and a Quafe center along with the improved shafts and pinion bearing.
You don't want to know how much I have in this, an it is still on the bench being assembled....
You don't want to know how much I have in this, an it is still on the bench being assembled....
Burning Brakes
Joined: Nov 2009
Posts: 1,157
Likes: 1
From: Oxford Pa
I put a C6Z diff in my 07 C6.. Forum member and sponsor Rim Kim did my install http://rktperformance.com/
All these launches were over 5k
Race Director
Joined: Aug 2005
Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
Same cooler as the Z06, I have the Z51 lines, but I don't know how it will all fit until we install the diff. I am going to keep the stock Z51 diff and install a complete new diff.
Racer
Joined: May 2010
Posts: 499
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From: Bensalem PA
Yes the european Z51's came with a side cover for a diff cooler. When I got my stage 3 RPM rear I was trying to figure out what the hell they sent me so I could order a trans brace for it. After doing some research it was european side covers so I had to order a trans brace for a normal c6 and notch part of the bracket for the cooler so that the brace would fit.
Safety Car
Joined: Jan 2004
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From: Pinellas Park Fl
St. Jude Donor '08-'09 & '12, '14
Race Director
Joined: Aug 2005
Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
The rear cover is the same as a Z06 that ahs the pump built in. I had the pinion machined by RPM to accept the drive for the pump. I bought a cooler, pump etc on the forum from a guy that took it off of a ZR1 diff.