3 rib diff

[Munch]

What makes the 3 rib diff better than the 1 rib? I must know every detail.

If you have a pic of the 3 rib that would be even better, I'm gonna crawl under my car and see what's there so it would be nice to know what I'm looking for.

Thanks

[wwomanC6]

Originally Posted by Munch

What makes the 3 rib diff better than the 1 rib?

2 ribs

[Munch]

Originally Posted by wwomanC6

2 ribs

This is the serious section of the forum.

[Y2Kvert4me]

Originally Posted by Munch

This is the serious section of the forum.

I don't believe we have one of those...


If your 2000 has the stock differential, it will be a 1 rib housing. The 3 rib case started appearing sometime during the 2001 model year.Not all 01s had them, but all C5s 02/newer came with them.

The extra ribs add a lot of rigidity to the housing, which by minimizing flex/distortion in extreme pressure operating conditions helps to keep everything within it in better alignment, and (hopefully) less prone to deflection and breakage.

It can be argued that it's usually not the housing itself that causes failure, but rather the breaking parts inside it causing the housing to break as a result (not uncommon). No matter, stronger is better in this case.


Here is a comparison shot of the 1 rib (left), and 3 rib (right) housings to illustrate the casting difference.

[Munch]

Originally Posted by Y2Kvert4me

I don't believe we have one of those...

This is true, my bad. Wendy you are forgiven.

Upon inspection it looks like I have the 3 rib. That's kind of what I thought seen as how it has the 3.42's.

Thanks!

[Sneaks]

Now, will the 3.42 ring and pinion work in the 1 rib diff?

[Munch]

Originally Posted by Sneaks

Now, will the 3.42 ring and pinion work in the 1 rib diff?

I don't know for sure but I thought I heard that the 2.73 case will not hold the 3.42's. On the same note all C5's had the 3 rib after 02 so maybe there are 2 different size cases or maybe I have no idea what I'm talking about. Most likely it's the latter.

[Y2Kvert4me]

There's no difference in the cases between A4 and M6 cars.

Either rib type of case can hold anything from a 2.73 to 4.10 ratio.
I believe the difference with the 2.73 gears is with the carrier that the ring gear fastens to. There is something dimensionally different about it, and this is why many vendors don't accept 2.73 boxes as cores, because it requires using either a new carrier, or some machining to accommodate the 3.x/4.x ratio gearsets.

Not totally sure on the exact difference, but the point being that's nothing ado with the housing casting, just incompatible parts within it.

[Eagleeye]

I heard three rib gives more pleasure...

[thegreenman]

Originally Posted by Eagleeye

I heard three rib gives more pleasure...

And last long time.

[Munch]

Originally Posted by Eagleeye

I heard three rib gives more pleasure...