:ro) Beware the so-called high performance oil treated air filters. K&N and Amsoil types. On the Duramax the mass air sensor is located right at the filter and in time it will get coated with enough oil particles from the filter to seriously corrupt it’s function. Mileage will suffer and a serious loss of power. If you insists on using such a filter be prepared to remove and clean the mass air sensor every 1,000 miles. I installed an Amsoil filter in my 2004.5 Duramax. I was unable to see any benefit other than the $123.00 it cost me at the dealers to find out why my truck wouldn’t pull a hill.

In my mind, the stickers that come with the K&N kits are the only things worth using.

What about the new AFE ProGuard7 7-layer media filter? They make a square factory replacement. Then you could just swiss-cheese the factory box for more airflow. I've seen it for sale for as little as $66.

So you guys are saying all aftermarker intakes/cone shaped filters suck?

gulchguy,
Did your truck do this after you re-oiled your filter, or when the filter was new?

I only picked up a shade under 5 hp on the dyno by yanking my stock paper filter and running with nothing in the air box. I say keep the stock paper in a cheesed box.

I can't seem to find the thread that had the air filter test done a year or so ago. Anybody have that data? :help:
JP

same thing happened to me when i cleaned my pg7. when i had a problem pulling, mike tomac was there, asked him about it. he said to unplug the sensor. i did and it was back to normal. got back home and cleaned the sensor with some eletric cleaner, and what do you know, back to normal. fyi, i still have the filter in there

The filter was new. The factory said they had some? problems with filters coming from the factory over oiled. I saw no indication of this when I installed it.

gulchguy,

Here's a little info for you folks. The main reason AFE is in existence is the owner had experessed interest in reformulating the K & N oil when he worked there to stop the mass air fouling problem. This idea was not considered important etc. So he got PO'ed and started AFE. Their oil is of a different formulation and does NOT cause any mass air problems.

The next innovation AFE came up with was Pro Guard 7, finally a reuseable washable filter that stops the dirt, looses a little flow to the 4 layer gauze filters but STOPS the dirt.

Do not expect any neck snapping HP gains from a intake system of any brand. What you will get is a better/quicker spool up on your turbo, lower EGT's and better MPG. It allows your programmer/module and exhaust system to work at their best efficiency. You add fuel you need to add air, you add air you need to get rid of it. No matter how you add it up an engine is still an air pump, you just add fuel to make it POP!!!!

Call su if you have any questions, we'll be glad to help.

Mark @ DPPI

Heartbeat, is this what you are looking for?

http://home.usadatanet.net/~jbplock/ISO5011/SPICER.htm

I had a AFE stage II and a Pro-Guard 7 filter on my 03 Duramax. I gained 2mpg towing my 30ft fifth wheel and definately noticed faster spool up on the turbo. I think it was worth it.

That could be true if your mileage comparison was done with a dirty/clogged stock filter.;) I had a AFE stage II and a Pro-Guard 7 filter on my 03 Duramax. I gained 2mpg towing my 30ft fifth wheel and definately noticed faster spool up on the turbo. I think it was worth it.

I saw no gains at all by adding my aftermarket filter.

Makes a cool noise though ):h

I still think over-oiling may be part of the problem. I experienced this years ago with a K & N on my old '94 GMC. I've since wised up to how much oil is needed on one of these filters and to date I've had no problems using the K & N on my '02 Dmax. Go easy on the oil and maybe this will help (I hope) - good luck.