M9 Issue
With the standard 9 inch I have never noticed a problem with the symptoms you're having. Your pinion angle should not be off, but that is what I would look at as well.
The factory length driveshaft will work for either the Moser 12 bolt or the Moser 9 inch, but we just recently decided to make the driveshaft for the 9 inch one inch longer, as we've noticed several that were on the short side. This would not create a problem but on the highest horsepowered cars.
http://www.exoticperformanceplus.com....html?item=541 Bob


