1-rib--3-rib.. Differential difference?
Thread Starter
Racer
Joined: Jan 2009
Posts: 393
Likes: 14
1-rib--3-rib.. Differential difference?
What is the difference of 1-rib and 3-rib differentials in C5? My 3.42:1 diff broke and I'm looking for a new one. I came across this rib-thing and I'm unsure if it matters in this case.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Check this out!! 
You might want to take a look at the following two Differential UP GRADE post. That much power,, you need all the help you can get. You already have the DIFF removed:
Nice at home doable upgrade that will not break the bank:
I got ALL my C6 ZO6 parts from Gene Culley www.gmpartshouse.com
- C5, ragtopws6 , Upgrading your C5 rear with C6 Z06 guts, : http://forums.corvetteforum.com/c5-g...-z06-guts.html
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- C5, Its_Go_Time, Output Shaft Install - Left and Right: http://forums.corvetteforum.com/c5-t...post1573407966
- C5 Differential Seal replacement: http://forums.corvetteforum.com/c5-g...on-photos.html
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-
You might want to take a look at the following two Differential UP GRADE post. That much power,, you need all the help you can get. You already have the DIFF removed:Nice at home doable upgrade that will not break the bank:
I got ALL my C6 ZO6 parts from Gene Culley www.gmpartshouse.com
- C5, ragtopws6 , Upgrading your C5 rear with C6 Z06 guts, : http://forums.corvetteforum.com/c5-g...-z06-guts.html
-
- C5, Its_Go_Time, Output Shaft Install - Left and Right: http://forums.corvetteforum.com/c5-t...post1573407966
- C5 Differential Seal replacement: http://forums.corvetteforum.com/c5-g...on-photos.html
-
-
Melting Slicks
Joined: Nov 2009
Posts: 2,922
Likes: 219
From: West Branch, MI
Hope this question relates to this thread as well. Definitely NOT trying to hi-jack this thread. How much HP can the stock differential handle safely? For example, can the stock A4 differential handle 400-500 rwhp safely without too many mods? How about the M6 differential? Can the 3 rib handle more HP than the 1 rib? Thanks gents! 
Melting Slicks
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
The 3 rib is a stronger case. Everything inside is the same. Except for the Z06 3-rib diff which says "SP" on the 3.42 badge. This is for the shot-peened or micro-polished gears they have.
The diffs are year specific. Early vetts got a single rib. Later got the three rib. Cant remember the exact year that the change over occurred.
An automatic is much easier on the drive train than a manual. But upwards of 500 whp and you are able to see problems. A manual needs some work at around 400whp.
For the OP, I would definitely order a stage 2 diff from RPM, RKT, or DTE. Since you have a 3-rib, they will build you a 3-rib and take yours as a core ($750). You are going to destroy another stock diff behind all that power. The stage 2 is good for 600ish whp with many parts even tested to 900whp, (like the C6 output shafts).
I ordered a stage 2 from RPM for my A4 3200 stall and Heads and cam build. Car may see 500-600 as an end goal. I shouldn't have to worry about outgrowing the diff.
The diffs are year specific. Early vetts got a single rib. Later got the three rib. Cant remember the exact year that the change over occurred.
An automatic is much easier on the drive train than a manual. But upwards of 500 whp and you are able to see problems. A manual needs some work at around 400whp.
For the OP, I would definitely order a stage 2 diff from RPM, RKT, or DTE. Since you have a 3-rib, they will build you a 3-rib and take yours as a core ($750). You are going to destroy another stock diff behind all that power. The stage 2 is good for 600ish whp with many parts even tested to 900whp, (like the C6 output shafts).
I ordered a stage 2 from RPM for my A4 3200 stall and Heads and cam build. Car may see 500-600 as an end goal. I shouldn't have to worry about outgrowing the diff.
Safety Car
Joined: Aug 2011
Posts: 4,449
Likes: 409
From: Portland OR
I believe 01 and later 3.42 were all 3 rib.
Mine came from an 01 6 spd coupe.
I rolled my own with the 4340 shafts and C6 clutches etc. It wasn't cheap, but I don't have to worry.
I'm calling it the RJS stage 2.3
Ron
Mine came from an 01 6 spd coupe.
I rolled my own with the 4340 shafts and C6 clutches etc. It wasn't cheap, but I don't have to worry.
I'm calling it the RJS stage 2.3
Ron
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Race Director
Joined: Dec 2006
Posts: 12,385
Likes: 2,906
From: Fort Worth, Texas
This is a 3-rib...
http://www.ebay.com/itm/97-04-Corvette-C5-GETRAG-Rear-Differential-3-15-Ratio-/140754604081?pt=Motors_Car_Truck_Parts_Accessories&hash=item20c5a0d031&vxp=mtrThis is a single rib...
http://www.ebay.com/itm/97-04-Corvette-C5-Rear-Differential-3-42-Gear-GETRAG-Used-OEM-GM-/290947564351?pt=Motors_Car_Truck_Parts_Accessories&hash=item43bdd3833f&vxp=mtr