Sorry, I should have used the term "carrier." The carrier is the piece that the ring gear bolts to, this is the Quaife part you're referring to. The parts that Travis (blackbird) and others have are case failures. This happens because the torsional force on the pinion and the ring gear causes the pinion gear to try to push toward the front of the car. The case is weak in the "snout" and the pinion puts so much pressure on that portion that it eventually breaks the case.Saturn Sky Forums: Saturn Sky Forum - View Single Post - What is the true potential of the Redline?
I saw some pics of one recently but today I couldn't find them.
This could happen for a number of reasons, my guess would be the pinion trying to climb the ring gear, which could be alleviated a couple ways, but is an issue from the factory, as evidenced by the noisiness of the 06 diffs. Different backlash would help this a little bit.
The reason the CTS differential units appear "stronger" is because of the lower gear ratios. There is much less stress in a 3.23 or 3.42 gear than there is a 3.73 or a 3.91. Less torque means less torsional pressure to push the pinion out.
Hope that makes sense. This is why GMTech made the brace that he made, it holds the front of the case onto the rear so the torsional pressure isn't as stressful on the case.