There rear tire wear is almost always from the ball joint on the wishbone link being worn. You can have 3° of neg camber without wearing the tire it's the negative toe while braking that causes the wear.

There was a recent thread where somebody that added adjustable links had rubbing like you described and figured out a fix. Factory links will not rub with any of the factory size tire options.

Also: unless there is some damage you will be able to get the car adjusted to spec without special arms unless you lowered your car it's the only time I'm aware of where the special arms are needed.

I've never seen an example of "can't get to spec" and "too much neg camber" that was inaccurately blamed on inside tire wear that wasn't either the wishbone link or the rear ball joint or both.

If the wishbone link is shot, it can be possible to still align the suspension when not moving but when you hit the brakes the loading of the suspension will steer the wheels outward add much as 2° and eat through tires very quickly.

When I replaced mine, I could move both the bad joints over 1.5mm that equates to well over 1° of steering motion!

I can't remember the exact trick the guy used to fix the rub but I would cross that bridge if it comes up. It should cure itself as you swap back to factory parts.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)