kreativ

As far as paper filters (not K&N) are concerned, are OE Toyota/Lexus air filters any better than, say, FRAM air filters from my local auto store?

Gs400TRD

fram are the worst. OEM is good, mobil 1 ($9), pure 1($5) are better.

kreativ

Gs400TRD - Sounds like you're talking about oil filters?

RON430

kreativ - Fram filters are set up for filtration not airflow. They do a decent job filtering but also have some of the highest restriction. And, to make things that little bit better, both increase as the filter has been used. The K&N has always been known for high flow and good filtration with the added feature that you can reclean and reuse it. There has been discussion lately of oil coming off the K&N and contaminating sensors but I have never seen any problems with K&Ns. My guess and past experience would be that the stock Toyota (Lexus) air filter would be a good piece and strike a good balance between filtration and flow. I just got a TRD catalog yesterday and TRD lists air filter elements, might be worth a call to Steve Ganz and see if the TRD element is available for the GS. I think Toyota has set the GS4 up to make its 300hp pretty much regardless of the filter restriction (within reason) so the choice is pretty much up to you.

kreativ

Ron430 - Good information, thanks.

aerodyne

FWIW, I'm noy going to a K&N untill the warranty has expired.

aerodyne

MGS4

Air filter test. Click the link

http://www.gtrowner.com/induction.html

kreativ

MGS4,

Thanks for the link. Interesting article.

adale

Just my two cents worth...I used a K&N on a turbo S70 Volve and after reading the various articles on the net did an oil test to see what was getting through the air filter. Sure enough the silicates in the S70 were almost three times as high as those found in a 4.0 liter naturally aspirated Ford using a stock air filter. I got rid of the Volvo and got a new GS300, after 20K miles installed an Amsoil airfilter. I did the oil test again at 25K and found the silicates were about 1/2 the level as the Ford. I am not trying to push Amsoil products or anything. I wanted to go with the reuseable filters because of the cost of the Volvo filters and the disposal issues of the old filters.

K&N does flow considerably more air than the stock filters at the cost of less filtration of fine particles, this is why they actually filter better after they have a film of dust on them.

Food for thought and please understand I am no petroleum or automotive engineer...just another regular car nut.

pat5000

FYI, My Amsoil filter fell apart after the first cleaning. I never had this problem with K&N.