For record purposes, the picture shows the lower (AC) belt tensioner (new and original). Part #11287512758. According to realoem.com it is for vehicles manufactured "from 9/2002" that have a mechanical tensioner. This is NOT the upper accessory belt tensioner.
Originally Posted by bluebee
That previous 318i post is unbelievable. What on earth happened to the education system in the years since I graduated from high school?
Anyway, a great thread today confirmed, in addition to what ElwoodBlues posted, there's yet another type of mechanical tensioner that looks different than the ones pictured prior.
Since the identification of the type of tensioners is visual, I'll repost the picture here from a 2003 BMW 525i.
Notice the lack of the raised molded nut. Instead there's a sunken Torx #60 indentation. Who knew!
2014 E84 X1
2006 E53 X5
2008 E70 X5
2003 E39 525i
2001 E46 330ci
2001 E46 325i