I'm not sure how to access and change the air filter. I believe there are some hidden clips, and the housing separates and comes off similar to the steps for some of the other MB's with the 350 engine. Right?

Technically, I'm not "due" for a change, but you know...

Thanks.

 

Exactly the same as all others with 350 engine.

There are two filter elements.

 

here

https://mbworld.org/forums/c-class-w...tallation.html

/thread

 

Agree! It should be just the just same install as on the C-Class.

 

Log on SLKWORLD.com There is post with illustrations how to change air filter. You can buy green filter from their store which much better than K&N.

 

Thanks for the tips. Some of the images from the K&N install thread don't show up. But I'll register with SLKWORLD and hopefully can see the steps there. Or I'll just search for the process with another 350 engine.

 

Benchbear, when you log on SLKWORD.com click on slk store and find green filter item. You may find thread how to install it. Tools you need I believe is torque screwdriver only.

 

Thanks all. Got it done based on "triangulating" from these multiple sources. Obviously very easy once you know how.
Some MB engine covers have some sort of "latch" near the firewall that I didn't want to miss or crack. The GLK 350 engine cover basically just pops off in two pieces - but you have to have faith that you aren't breaking anything by just pulling. :-)
Thanks again.

 

Anyone know if the 2011 air filter is the same as the 2010. I assume it is but just checking. Plan on getting a set.

 

Yes

 

I am trying to figure out how to change the cabin air filter on my GLK 350. Can someone help ASAP??!! THANKS!!!

 

Using the search feature would helped yourself ASAP: https://mbworld.org/forums/glk-class...in-filter.html You're welcome.

 

Can anyone confirm if using a high performance air filter you will see a gain in performance and fuel eco and will it not throw any errors becuase of the oil on those filters and you end up having a problem that merc won't warranty it becuase of using a different filter?

 

Total waste of money for very little, if any, power gain. Plus they're real messy to clean and re-oil. Yuck! Stick with OEM or Mann filters. (They're the same thing.)

 

As you yet have had no replies to your three concrete questions, I'll give it a try - given you are referring them to your GLK.

K&N Air Filters are renown, both as OEM replacements - and High Performance replacements. Note what their claims are, with regard to gain in performance: http://www.knfilters.com/cold_air_intakes.htm.

K&N High Performance replacement filter kits are not available for the GLK.

K&N even state: "OEM replacement air filters generally add 1-4 horsepower"

Note bullet no. 9 on the page from K&N Engineering: http://www.knfilters.com/filtercharger.htm

Note K&N letter: "Letter from K&N Regarding U.S. Vehicle Warranty and K&N Replacement Filters": http://www.knfilters.com/warrantyletter.htm.

Quite impressive warranty terms (note the second last section of the letter), isn't it?

 

^ Actual field tests show otherwise.

 

As you are referring to the post regarding K&N filters, would you kindly provide us with references to following:

• What actual field test “show otherwise” than the content of the actual K&N article as referred to above?
• What actual field test “show otherwise” than K&N filter does “Work with Original Equipment Manufacturer Vehicle Electronics”?
• What actual field test “show otherwise” than K&N warranty claim "Will NOT Void Vehicle Warranty"?

 

I'm speaking of their claim for more HP, (very minimal if any) and better fuel mileage. Our dyno tests have shown that these claims are more hype than anything else.

 

References, please, to the "Our dyno tests have shown that these claims are more hype than anything else.", regarding the K&N filters, in question, when you responded with your "^ Actual field tests show otherwise".

 

From

Debunking the K&N Myth – Why OEM Is Better

For decades, the aftermarket hot rod, racing and tuning communities have relied on oiled-media filters to free up that extra few horsepower.In fact, it’s often one of the FIRST modifications many automotive enthusiasts do to their car.

This report shows, with empirical data and sound reasoning, why OEM filters perform better in a variety of areas.

Special thanks to Arlen Spicer and all others involved in making this information available.

A note from the author:
The reason I started this crusade was that I was seeing people spend a lot of money on aftermarket filters based on the word of a salesperson or based on the misleading, incomplete or outright deceiving information printed on boxes and in sales literature. Gentlemen and Ladies, Marketing and the lure of profit is VERY POWERFUL! It is amazing how many people believe that better airflow = more power! Unless you have modifications out the wazoo, a more porous filter will just dirty your oil! Some will say ” I have used aftermarket brand X for XXX # years with no problems. The PROBLEM is you spent a chunk of change on a product that not only DID NOT increase your horsepower, but also let in a lot of dirt while doing it! Now how much is a lot? ANY MORE THAN NECESSARY is TOO MUCH!

Others are persuaded by the claims of aftermarket manufacturers that their filters filter dirt “better than any other filter on the market.” Sounds very enticing. To small timers like you and me, spending $1500 to test a filter sounds like a lot. But if you were a filter manufacturer and you believed your filter could filter dirt better than any other media on the market, wouldn’t you want to prove it? Guess what. Test your filter vs. the OE paper. It will cost you $3000 and for that price you will have the data that you can use in your advertisements. Your investment will be returned a thousand fold! EASIER than shooting fish in a barrel! So why don’t these manufacturers do this? Hmmm? Probably not because they would feel guilty about taking more market share.

Now I am not saying that ALL aftermarket filters are useless. A paper filter does not do well if directly wetted or muddy. It may collapse. This is why many off-road filters are foam. It is a compromise between filtering efficiency and protection from a collapsed filter. Now how many of our vehicles collapse their filters from mud and water?

However, if a filter is using “better airflow” as their marketing tool, remember this….Does it flow better? At very high airflow volumes, probably. BUT, our engines CAN’T flow that much air unless super-modified, so what is the point? The stock filter will flow MORE THAN ENOUGH AIR to give you ALL THE HORSEPOWER the engine has to give. And this remains true until the filter is dirty enough to be recognizeable. At that point performance will decline somewhat. Replace the filter and get on with it.

Hopefully the results of this test will do 2 things. Shed some light on the misleading marketing claims of some aftermarket manufacturers and/or give us new insight on products already on the market that are superior to our OE filter.

SCOPE:
This report presents the results of an ISO 5011 test of several air filters designed for the GM Duramax Diesel. The test was independently performed under controlled conditions using a $285,000 machine at Testand Corp of Rhode Island (manufacturer of the machine).

Arlen Spicer, a GM Duramax Diesel owner/enthusiast organized the test. Testand offered to perform the tests at no charge. (These tests typically cost approx $1700.00 per filter).Ken (and employee of Testand), a Diesel enthusiast and owner of a Ford Power Stroke Diesel, shared Arlen’s interest in performing an accurate unbiased test of different types and brands of diesel engine air filters.

The filters used in the test were purchased retail and donated by Arlen and other individual Duramax Diesel owners. The detailed reports from the test have been compiled and are presented in the following pages. The final pages of this report present the behind the test.

ISO 5011 Test:
The ISO 5011 Standard (formerly SAE J726) defines a precise filter test using precision measurements under controlled conditions. Temperature & humidity of the test dust and air used in the test are strictly monitored and controlled. As Arlen learned in attempting his own tests, there are many variables that can adversely affect filter test results.A small temperature change or a small change in humidity can cause the mass of a paper filter to change by several grams.

To obtain an accurate measure of filter efficiency, it’s critical to know the EXACT amount of test dust being fed into the filter during the test. By following the ISO 5011 standard, a filter tested in Germany can be compared directly compared to another filter tested 5 years later in Rhode Island. The ISO 5011 filter test data for each filter is contained in two test reports; Capacity-Efficiency and Flow Restriction.

Capacity and Efficiency:
The Capacity and Efficiency test report presents the test results of feeding an initially clean filter with PTI Course Test Dust (dirt) at a constant rate and airflow. The course test dust has a specific distribution of particle sizes ranging from less than 2.5 microns to greater than 80 microns (see table below).

Every filter is initially tested at 350 CFM and the Initial Restriction or differential pressure across the filter is recorded in IN-H20 (Inches of Water). The filter is then tested by feeding test dust at a nominal rate of 9.8 grams per minute with a constant airflow of 350 CFM. The test is continued until the flow restriction exceeds the Initial Restriction + 10 IN-H20.

At this point the test is terminated and the amount of dust passed through the filter (Accumulative Gain) is measured.Dirt passing through the filter is captured in the Test Station’s Post Filter. The exact amount of dirt passed is determined by measuring the before and after weight of the Post Filter.

Similarly, the amount of dirt retained by the Filter under test – Accumulative Capacity – is measured by taking the difference between the before and after weights of the Filter. From these results the overall % Efficiency of the filter is calculated.This test also indicates how long a Filter will last before replacement is required (or cleaning for reusable filters).

Flow Restriction:
This report presents flow restriction of a clean filter resulting from an increasing airflow. The differential pressure restriction across the filter is reported in inches of water (IN H2O) versus Air Flow in cubic feet per minute CFM.

Data from these reports has been compiled and presented in the following bar graphs, plots and data tables.

Filtering Efficiency:
Filtering efficiency is a measure of the filter’s overall ability to capture dirt.

Accumulative Capacity:
“Accumulative Capacity” is a measure of dirt holding/loading capacity before reaching the maximum restriction limit. Initial Restriction + 10 IN-H20.

Accumulative Gain:
“Accumulative Gain” is the total amount of dirt that passed through the filter during the test.

(Note: The Purolator was reported to have a seal malfunction during the test and passed more dirt than it would have with a good seal.)

Initial Restriction:
Initial Restriction is the Filter under test’s resistance to flow at 350 CFM.

Dirt Passed Versus Total Test Time:
This graph shows each the duration of each filter’s test versus dirt passed (Accumulative Gain).

(Note: The Purolator was reported to have a seal malfunction during the test and passed more dirt than it would have with a good seal.)

In the chart above it’s important to note the different test durations for each filter. The AC Delco filter test ran for 60 minutes before exceeding the restriction limit while the AMSOIL and K&N tests each ran for 20 and 24 minutes respectively before reaching max restriction.

In 60 minutes the AC Filter accumulated 574gms of dirt and passed only 0.4gms. After only 24 minutes the K&N had accumulated 221gms of dirt but passed 7.0gms.

Compared to the AC, the K&N“plugged up” nearly 3 times faster, passed 18 times more dirt and captured 37% less dirt. See the data tables for a complete summary of these comparisons.

Dust Loading:
The dust loading curves show graphically how each filter responded to a constant 9.8 gms/min dust flow before reaching the maximum restriction limit.

It’s interesting to note the shape of these Dust Loading Curves. The AC and Baldwin filters each had near linear responses until reaching maximum restriction. Restriction for these filters increased at a constant rate versus the 9.8 gms/min dust feed rate.

The other filters, most notably the oiled reusable types, had an exponential loading response before reaching maximum restriction. These filters had a lower initial restriction, but they became exponentially more restrictive under a constant flow of dirt.

This runs counter to the “myth” that oiled media filters actually “work better” as they get dirtier.

Also notice the length of the curves as it shows the relative test time for each filter (time to max restriction).

Restriction to Flow:
The Restriction to Flow curves graphically show how each “clean” filter responded to a steadily increasing flow of air up to 350 CFM.

The Flow Restriction response curves for each filter have the same basic shape. However, note how the AC Filter, which passed the smallest amount of dirt and had the highest dirt capacity and efficiency, also had the highest relative restriction to flow.The less efficient filters correspondingly had less restriction to flow.

This illustrates the apparent trade-offs between optimizing a filter for dirt capturing ability and maximum airflow.

 

An interesting report as such, and even more “powerful” when the six graphs goes with it.

However, it’s not the reference as asked for; it is not yours dynamometer tests (“Our dyno tests have shown –“), but presumably nonbiased tests using filters designed for the GM Duramax Diesel. And it is not "Actual field tests", like ones conducted by putting filters in a car and running them according to criteria as set forth. They are done in a testbench, following ISO 5011 testing procedures, like K&N does in their test facilities.

What this exchange of views started from, is your comment on my reply to a poster, with regard to gain in performance of K&N filters, reference made to a GLK. I referred to (general) statements made by K&N and you to tests of a Duramax filter. To really find what gain (or not) in performance a K&N GLK air filter has, one can use the K&N offer: “Specific testing documents that support any particular claim are available upon written request.”. Using OEM filter am I unfortunately not in position to do so.

And, with reference to your report, I noted (a totally disconnected) statement from the author: “Now I am not saying that ALL aftermarket filters are useless.”.

 

I wish I had those old tests we did back in the mid 90's... sorry

 

Neither of them would work in your struggle for disapproving the K&N horsepower and torque claims – gain in performance –, referred to in my post with regard to GLK, as the suvlet was released in 2009. Note your post: “^ Actual field tests show otherwise.”

As you are well aware of, the “report” “Debunking the K&N Myth – Why OEM Is Better” is not a test of gain in performance, but a performance test of the filter as such.

The K&N claims with regard to horsepower (and torque) are based on testing of an actual vehicle on a dynamometer before and after a K&N product has been installed.

So, in compliance with my request for references, and to overcome the busted myth of yours: "Our dyno tests have shown that these claims are more hype than anything else.", I suggest you put the GLK on your dynamometer, test it with a (brand new) OEM air filter, and then a K&N filter for comparison.

“Specific testing documents that support any particular claim (in this case that should be gain in performance) are available at K&N upon written request.”. Ask for the GLK relevant one, compare with your own dyno test - and then you’ll see whether the “^ Actual field tests show otherwise.” – or not.

Until then I still think any K&N claims with regard to gain in performance at filter replacement, are valid.

 

^ What ever lights your fire!

 

You’re wrong again. Totally : No fire, not even smoke, just trying to get nonverified statements corrected. As I have ignored “accusations” from you before, without responding to them, I’ll step down to your level – for once.