The K&N 33-2959 is a washable, reusable panel filter for the 3.0L L6 diesel in the BMW X5 and X6. K&N washable, reusable High-Flow Air Filters use layered, oiled cotton media meant to improve airflow while capturing contaminants. The manufacturer rates overall filter efficiency at up to 99%, so you keep filtration while gaining flow. Because the filter is reusable, the cost is a one-time purchase instead of repeated disposable replacements. Each performance air filter is backed by K&N's No-Hassle Lifetime Limited Warranty. The manufacturer also says the filter should only need cleaning every 75,000 miles under normal highway driving conditions. Owners searching for a BMW X5 3.0d intake upgrade or a reusable diesel air filter for X5 xDrive35d will find this a straightforward option.
This is a drop-in replacement, so you do not need to modify the intake. K&N drop-in replacement filters are designed to install easily into your factory air box. Installation is a simple swap, but check the airbox type first. The manufacturer notes that some BMW airboxes use a tray design, where you should hold the filter in place while reinstalling the lid so it does not fall out. A K&N filter also needs firmer clip pressure than a stock foam seal, so make sure the filter, lid, and base are aligned before fastening the clips.
The manufacturer lists this filter for the BMW X5/X6 L6-3.0L DSL for 2007-2010. Fitment details vary across sources for later model years, so confirm your year and engine with the manufacturer before ordering.
The manufacturer states the filter only needs cleaning about every 75,000 miles under normal highway driving conditions. Harsher conditions, such as dusty roads, will call for more frequent inspection.
This is a drop-in job that most owners can handle in a short session. Remove the stock filter, wipe out any dust in the airbox, and seat the K&N filter fully. Owners on user forums report that the tray-style airbox on some BMWs is the trickiest part, so hold the filter in place while you close the lid. Do not force the lid or clips; if the lid is misaligned, the airbox can crack. Check the seal on the lid before driving.
