I am experiencing almost the exact issue described in this tread on my 2008 BMW 328xi (~42k miles): http://www.e90post.com/forums/showthread.php?t=175885 Click when changing directions and when going on/off the throttle - but in my case I'm hearing it from the front whereas most others report it coming from the rear. How people are describing this issue in that thread sound exactly like how I am experiencing it just from the back instead of the front. I replicated it for a couple different shops but they seemed hesitant to make any recommendations. What I am thinking is that I may be experiencing similar slop with the flanged coupler of my front diff. Any thoughts?
Is that the only time you hear the noise, and is it temp related? Are you sure the noise is from the front?
It's pretty much happens all year round and regardless if I've just started up the vehicle or it's been running for a while. It also happens when going on/off of the throttle right around 20mph - the exact symptoms of people who say their rear click sound were fixed by that TSB of greasing the diff flange splines - except my car is an xi. Definitely doesn't sound like its coming from the rear for me - feels like somewhere below me and up front a little.
Well to make sure the noise is coming from the front diff I would have a friend shift to make the noise then take a really long screw driver or extension and put it to the front diff and your ear to the other end and see if you can hear the noise.
