Review on BMW Engine Upper Radiator Coolant Expansion Tank Hose: 2008-2013 128i, 2006-2011 323i, 2006 325i, 325xi, 2007-2013 328i (OE # 17127618510 17127565093) by Djuan Thompson

If you have yet to replace this hose on your N54 then this is definitely one to consider as it is so cheap. I made the mistake of not listening to several people's claims that it was thin tubing and had to wait for the tubing before I could ride again. Despite the expectation, it seemed small at first, but it actually fitted perfectly and has been working ever since. The plastic that actually sits between the hoses is very brittle and often cracks over time, so buy something before that happens. (It literally takes >10 minutes to install and you lose very little coolant) :) 5 stars overall.