I power washed my cabin filter
 

then let it dry in the sun, I think it came out great and I will re-use it.

besides criticism about being cheep, see any problems/issues?

Hmmm, I am curious to know the answer aswell.

Chances are your filter is simply not as effective anymore because the activated carbon is probably "saturated." Or maybe I am am confused and it does not work that way at all...just a guess. And from my fishtank cleaning days, activated carbon can only go through so many washes/filter cycles.

I skipped buying the 60 dollar filter and instead bought the engine air filter on my last trip to the dealer.

Yes, you are cheap. :nanana:

$60? Buy a non-OEM generic replacement. Somehow, I don't think that washing a disposable filter is very effective. :tsk:

They had these Mann filters with charcoal on Amazon for $23 bucks a month or two ago.

If you are really cheap, you MAY be able to wash them by hand as long as you let them dry completely before using. It sounds like power washing may be pretty harsh on the filter material. I wouldn't wash mine. One and done.

These fit the E53:

Amazon.com: Mann-Filter CUK 5366 Cabin Filter With Activated Charcoal: Automotive

Buy two or a Mann Oil Filter, for free shipping if you don't have Amazon Prime :)

Thanks for the tip! I just ordered the cabin filter and a K&N engine filter for $63 with free shipping from Amazon. This is a very simple replacement that will take no longer than 15 minutes or so. Now my family and our X5 can breathe cleaner air on our way to our Virginia Beach vacation!

Interesting info about the cabin filter.. I will have to read the manual and see when it supposed to be replaced .. I cant tell the difference in air.. Its just hot here .. And enjoy your trip to va beach. If you need some excitement go to ocean breeze water park.. they have gokarts there. If you catch a breezy day mt trashmore is nice but they just had a report of 2 wolfs there about a month ago.

Saw them on one of our sponsors websites here for only 15 bucks.
Ebay even has them for 13 bucks and free delivery. But I think I might really cheap out and try washing mine too....or just blowing compressed air gently thru it! LOL.

I found them on ebay for $12 CABIN AIR FILTER bmw X5 2000 2006 2005 2004 2003 2002: eBay Motors (item 140434790231 end time Aug-31-10 02:22:20 PDT)

x5 cabin filter items - Get great deals on eBay Motors, BMW items on eBay.com!

$16.60 with shipping (whereas you can get free shipping from Amazon with a $25 order). Also, I'd be leery of the quality of these filters. OTOH, Mann is a known OE supplier.