Here is a Cabin Air Filter Replacement DIY for a Second Generation (2004-2009) Lexus RX

Works For:
2004 Lexus RX
2005 Lexus RX
2006 Lexus RX
2007 Lexus RX
2008 Lexus RX
2009 Lexus RX

Lexus RX includes RX 330 and RX 350

Source: ClubLexus

Having benefited time and time again from great advice offered up by other posters, thought I’d return the favor a bit by putting together a quick guide for replacing the cabin air filter for the second generation (2007 RX350 in my case). Pretty straight-forward process, please find as follows:

Necessary goodies:

• Air filter — I opted for the Fram FreshBreeze (model# CF10132). Not sure if the activated carbon does much, but it was conveniently available at Walmart, or online (e.g. rockauto.com). <$15
• Pliers (optional) — Ideally something with relatively wide jaws, I used a slip-joint.

Pop open the glove box and at the upper left and right hand outermost corners, there is a plastic pin. In reading some prior threads, these are usually very tight coming out of the factory, so I needed pliers to twist and loosen them. (To prevent damaging/scratching the pin with the jaws of the plier, the tabs can be insulated with a plastic bag.) The left pin was loosened in the counter-clockwise direction, whereas the right pin in the clockwise:

It appears the pin didn’t have to be completely pulled out, just loosened a touch. Then, some gentle tugging on the walls of the glove box downwards/outwards allowed for its release. Here’s the full pin if one were to disassemble it completely:

With the glove box released, the filter holder (white) is revealed. Push inwards on the left/right tabs to release the holder.

The filter holder with dirty filter membrane:

Empty filter holder ready for new filter:

Now, place the replacement filter in the holder, noting the direction of air flow — air flows from top to bottom:

Snap the filter holder back in the chamber and twist-lock the glove box pins to complete the process.

Hope this helps!