barrykaye

Hey Guys,

Thinking of replacing the stock air filters in by '05 C240 Wagon with K&N filters. I put K&N's on my '04 V-8 Explorer and saw an increase of 1 -1.5 MPG. Any reason not to replace the stock filters? Warranty issues?

Thanks for your help.

sosh

Its likely this will create a shorter life span for the MAF. I do not believe that it will give you any added benefit other than a lighter wallet. Most all of this stuff is snake oil. Perhaps the reason your other vehicle showed a mileage increase was that your OEM filter was dirty. I also believe that the OEM MB filter does a fine job both in filtering and air flow.

SDR

Patently false. The MAF problem is caused by overoiling the filter. The increased mileage is not a placebo effect nor the result of replacing a dirty filter with a clean one or you'd see the same increase every time you replace the OEM. I have always used the K&Ns, NEVER had a MAF problem and have measured fuel economy improvements on my gas guzzling Expedition. I am a meticulous, mechanically inclined, **** retentive car owner. You can eat off the engine in my Expy and the filters were regularly replaced prior to the K&N install.

barrykaye

Sosh, I respectfully disagree. On my 04 Explorer V-8 (which I traded in for the C240), I was averaging 16 - 16.5 MPG. I drive 25-30,000 miles per year, 75% highway, 25% city. I too am meticulous about the maintenance of my vehicles - all service performed by the dealer at the factory recommended intervals and always Mobil 1 in the crankcase. At approximately 40,000 miles I put in the K&N filter. I saw an almost immediate increase in avg MPG to 17.5 which held until I traded it last week with 73,000 miles on the odo.

The C240 seems to be more complex than my Ford which is why I am being cautious. Probs with the MAF and any warranty aggrivation from MB are my main concerns about doing this. Is there anyone else out there that has successfully done this or are there any certified MB Techs out there that can comment?

SDR

Becase my knee jerk reaction (please accept my apology for that!) didn't make it clear, I do run the K&N on all 3 of the Benz's too. No problems at all.

Moviela

I use K&N in both my wagons. It does not spoil the Mass Air Flow sensor, improve gas mileage, nor yield faster acceleration. It does clean the air entering the engine better than the stock Mann paper filter. I have 20,000 miles on one car, and have no problems. Hardest part of the install is ripping open the plastic bag they are packed in.

For B service, I put the stock filter in, and let them change it, no worries with warranty for when the MAF does fail.

barrykaye

Thanks to all for your input. You too Sosh. Different opinions are what these forums are all about. Moviela, I am surprised that you didn't see any increase in fuel effeciency. I am ordering my filters today and will post the results when I have some decent info to offer.

vettdvr

I have use K&N on my corvette for 5 years and will switch to K&N on the E500 also. I agree.. if you OVER oil you might have a MAF problem. This is not a filter item but how you service them. I have never had an issue w/ K&N.

Jim

Fifth Ring

True, but you'll never have an over-oiled OEM filter.

SDR

Can't argue that point.
How about this: never drive your car and you never have to replace the air filter