I am considering a diff upgrade to a 3.23. I currently have a 2.93 final drive on my new 330i (6 speed manual tranny). For anyone who has upgraded their 330i final drive, I notice that Dinan offers 3.15. They content that higher ratio's may cause problems with DSC and/or ADB. There is a concern that traction control will get confused with shorter final drive. Anyone have problems with on board computer or DSC associates with differential upgrades?