Diff change
Thread Starter
Intermediate
Joined: Jun 2023
Posts: 25
Likes: 1
From: BIRMINGHAM AL
Diff change
I have a base 97 automatic with ls6 intake, cold air intake, long tube headers & x pipe cat delete, secondary air delete. I want to swap my 2.73 differential for a 3.15 I realize it’s not that big a jump but wanted to ask if it’s ok to swap pretty sure my stock differential is 1 rib would it matter if the new differential is a 1 or 2 rib? Any feedback would be greatly appreciated!
Racer
Joined: Oct 2021
Posts: 324
Likes: 157
From: Maine
I had a local guy re-program my shift points, he said he found all the info on HP tuners forum/help group. (he downloaded a tune someone gave him).
your speedo will be normal because the sensor is located by the axel. he said the shift points changed by about 15%.
your speedo will be normal because the sensor is located by the axel. he said the shift points changed by about 15%.
Melting Slicks
Joined: Aug 2007
Posts: 2,583
Likes: 415
From: Erwin, NC
I have a base 97 automatic with ls6 intake, cold air intake, long tube headers & x pipe cat delete, secondary air delete. I want to swap my 2.73 differential for a 3.15 I realize it’s not that big a jump but wanted to ask if it’s ok to swap pretty sure my stock differential is 1 rib would it matter if the new differential is a 1 or 2 rib? Any feedback would be greatly appreciated!
Did they make a 2-rib diff? I thought it was only the 1-rib and 3-rib.
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Joined: Oct 2008
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From: Whitby Ont.
- What it is: The "2-rib" designation refers to the appearance of the aluminum case on the rear differential, which has two visible ribs on its surface.
- Models: This type of case was used in some C5 Corvettes, including those with 2.73 or 3.23 gear ratios.
Melting Slicks
Joined: Dec 2004
Posts: 2,847
Likes: 1,144
From: Sleepy Hollow- NJ
Guys, it's 1 rib diff or 3 rib diff. There isn't a "2 rib diff". Yes, the 3 rib has more structural rigidity but just as many 3 ribs grenade as do the 1 rib. Typically when the cases crack they crack around output shafts. Not at the ribs in the casing. And no, it does not matter if your original diff was 1 rib when replacing with a 3 rib. They are interchangeable.
I've had to swap diffs out a few times after cracking the case at the output shafts on two separate diffs with 4.10 gears and one with stock 3.42. And stock diffs only come in 2.73 or 3.15 for the A4. And 3.42 for the M6 cars.
The diff case design was 1 rib for the earlier model C5s but changed to 3 rib on the '01 Z06. Then all '02 up cars got the 3 rib. All Z06 diffs came with 3 ribs and shotpeened gears.
I've had to swap diffs out a few times after cracking the case at the output shafts on two separate diffs with 4.10 gears and one with stock 3.42. And stock diffs only come in 2.73 or 3.15 for the A4. And 3.42 for the M6 cars.
The diff case design was 1 rib for the earlier model C5s but changed to 3 rib on the '01 Z06. Then all '02 up cars got the 3 rib. All Z06 diffs came with 3 ribs and shotpeened gears.
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Guys, it's 1 rib diff or 3 rib diff. There isn't a "2 rib diff". Yes, the 3 rib has more structural rigidity but just as many 3 ribs grenade as do the 1 rib. Typically when the cases crack they crack around output shafts. Not at the ribs in the casing. And no, it does not matter if your original diff was 1 rib when replacing with a 3 rib. They are interchangeable.
I've had to swap diffs out a few times after cracking the case at the output shafts on two separate diffs with 4.10 gears and one with stock 3.42. And stock diffs only come in 2.73 or 3.15 for the A4. And 3.42 for the M6 cars.
The diff case design was 1 rib for the earlier model C5s but changed to 3 rib on the '01 Z06. Then all '02 up cars got the 3 rib. All Z06 diffs came with 3 ribs and shotpeened gears.
I've had to swap diffs out a few times after cracking the case at the output shafts on two separate diffs with 4.10 gears and one with stock 3.42. And stock diffs only come in 2.73 or 3.15 for the A4. And 3.42 for the M6 cars.
The diff case design was 1 rib for the earlier model C5s but changed to 3 rib on the '01 Z06. Then all '02 up cars got the 3 rib. All Z06 diffs came with 3 ribs and shotpeened gears.
