[technician117]

Originally Posted by thxbuff2001

This write up perfectly explains why my e39 m5 is smoother than my f10 m5. They said bmw removed the cdv on my e39 m5 but they kept it on the regular e39.

https://www.zeckhausen.com/catalog/index.php?cPath=6562

Correct. The E39 M5 never had a CDV unlike all other models of the time (save maybe the M3).

For the F10, spend the money on the modified valve if you like, but I just removed it and reinstalled the line. There is plenty of "length" in the hose to make up for there not being a valve in place. Bleed the line and you're GTG.