I think 7500mi intervals are good for our tuned cars and it allows BMW to pick up the tab on every other oil change. I was surprised to see how long the additives last in the BMW Castrol oil, considering how hard and hot our cars run.
Has anyone had to add oil between changes? I know it's a common thing on the ///M cars but the N54 doesn't seem to burn oil--it just spits it through the PCV.
I'm curious what the factory intercooler looks like when it comes off. I'll install a BSH catch can if it looks like the intercooler or charge pipe is starting to collect oil.