Unless all of those millions of kilometers were on the original engine I don't see how this fact is relevant here. You could run a car with no air filter for 4 million km, you would just have to rebuild the engine more times than if you did run a air filter.

So far I have not seen any data that shows that cotton gauze filters are less efficient at catching particulate matter than a stock paper filter...just a lot of opinions and speculation.


I could go on, but you know what they say about arguing on the internet...


To each his (or her) own.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

This vehicle was maintained to MB standard at all times...

The total body miles is 2,858,307 with a total of three engines.

Each engine went roughly 952,769 miles.

Please explain why this is not significant data, directly impacting on this topic.


Here is the nearest to public test data I have found.
http://www.bobistheoilguy.com/airfilter/airtest3.htm

Engine milage is relivent, body milage not so much.

Now...anyboody have some filtration efficency data?

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

All of the major auto manufacturers have run full spectrum testing on these filters.
NO, you may not see the data, the files are confidential internal industry information.

The answer is simple; how many factory delivered vehicles arrive at the dealer with a K&N filter???

Not many,...but a K&N filter costs around $35 vs $8 or so for a stock filter. The 2000 Ford Mustang Cobra-R came with a K&N filter, as does the Apache helicopter. If they are good enough for aircraft use (especially aircraft such as a helicopter that operate in dusty conditions) then they are good enough for me.

There is data on the link I posted a few posts back.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

The two engines you selected are extreme high performance (extreme short life) GASOLINE engines, and I fail to understand how they have any connection with a Mercedes Benz diesel.


The Apache helicopter is powered by two General Electric GASOLINE turbine engines, which has no slightest relevance to any possible automotive air filter application, (these are jet engines)...

The 2000 Ford Mustang Cobra-R is an extreme high performance GASOLINE track and street toy, never designed for driving on average roads in the USA.

Note:
A K&N filter costs around $3 inside the OE price structure.

If they were better AMG would use them. Think they would skimp on a little $30 air filter on a $100,000 E63?

Mercedes, AMG, Ferrari, Porsche, Audi, Jaguar, Rolls Royce, Bentley, Lambo, BMW, M, Range Rover, Zonda, Honda, Toyota, Lexus, I could go on.

Find me one high performance money is no object car that comes with a K&N from the factory? Certainly if the HP gain was there they would use them, provided they did not hurt engine life. Toyota is big on low maintiance and they do not use them.

I submit to someone this. Put any MB on a dyno, do one run with a brand new stock factory filter. Do a second run with a new K&N. I bet you there is no difference, or its so small you would need a drag strip with good timing lights to notice.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

What is amazing about Mr. McClures statement is that test were done by his LAB and an independent LAB. The key word here is LAB abd not 5yr real world testing. Now, I run the stock filter on the MB but on my Ford, I run a Donaldson 4" which is a big rig filter. And if that paper filter is good enough for those multi-million machines then I figure it is good enough. Most of the people with Cummins, Navistar and Duramax engines in their light duty trucks do not like K&N or any oiled type filters because they DO NOT filter efficiently enough for full time use.
Bud

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1987 300D Turbo, 175k mi., 1998 BMW 323i Convertible, 1997 F250 4x4 7.3L PSD

I never claimed that they would cause a power increase, just that they filter as well as a stock filter.

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1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

Please explain why this is not significant data, directly impacting on this topic.

Its not significant data simply because it was not scientifically tested or collected. It is anecdotal evidence.

And here is some more anecdotal evidence....

I run a K&N on my work truck and the MB. The reason is conveinence. The MB broke 3 air filter mounts and countless rubber isolators. I had changed the motor mounts, installed a rack damper pin, etc. etc. to keep the engine from shaking the air filter loose. Nothing worked. I opted to install a custom K&N setup. No problems since.

GM opted to install a fairly crappy flat panel air filter housing on my work truck. They are notorious for not sealing well, letting dirt in, etc. Servicing it requires unbolting the entire housing and putting it on a bench to get it to seal reliably. I installed an aftermarket K&N setup. Easier to clean, service, etc.

I have three oil analyses before the K&N installation and three after for each vehicle. There was NO increase in contamination, notably silica, or any other matter after the K&N installation on either vehicle. I test every other or every third oil change and they continue to test clean. Conclusion, and the lab agrees, is the K&N is doing at least as good a job filtering as the stock filters. Good enough for me.

Why did I go to all this trouble? I was tired of reading all the opinions on K&N type filters and wanted to see for myself. If my experience had shown the K&N inferior I would have removed them and posted about that. RT

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When all else fails, vote from the rooftops!
84' Mercedes Benz 300D Anthracite/black, 171K
03' Volkswagen Jetta TDI blue/black, 93K
93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K

How clean are the tubes after the filter? It will take a few oil changes to see any differences in wear but dirt should be seem pretty quickly.

BTW, do you still have the airbox from your GMC and would you be willing to part with it?

The intake tubes are clean, maybe light oil but no grit/dirt. If there is no increase in dirt/particles in the oil then there is no increase in wear. Yes I still have the air box for the GM. Not sure if I want to part with it. I do have a complete airbox from a 94-98 Dodge Cummins truck that I planned to replace the GM with. These are not cheap and tough to find in the boneyard. Email if interested. RT

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When all else fails, vote from the rooftops!
84' Mercedes Benz 300D Anthracite/black, 171K
03' Volkswagen Jetta TDI blue/black, 93K
93' Chevrolet C2500HD ExCab 6.5TD, Two-tone blue, 252K

If there is oil in there, likely the filtering is adequate.

Proper tests (with proper test filters under the stock or K&N filter) show that unless oiled enough to deposit significant amounts of oil on the fine filter, the K&N will pass significantly more particulate matter, and even when oiled correctly do not filter as well as an OEM filter. AFtermarket paper filters aren't all that good, either.

Notably, when properly oiled, the K&N craps up pretty fast and the air flow falls off.

The filter support in a K&N, unoiled, is the equivalent of running the engine without a filter in the stock housing -- only sand sized stuff won't go through. The oil provides the bulk of the filtering action, the mesh only supports it.

Horsepower improvements are imaginary EXCEPT at high rpm/wide open throttle, which is the only time the pressure drop across the stock filter significantly restricts flow, if then. This is also the time when a K&N will pass the most dirt....

Modern air filter boxes aren't just a box stuck on the top of the carb and I'm willing to bet that most of the fancy pipe with right angle bends K&N "custom" intakes produce considerably more flow resistance that the stock box.

Air flow in a gasoline engine (turbo or not) is quite low except at wide throttle opening/high rpm -- remember vacuum? Diesels usually use the most air at fast idle, with flow dropping off due to pumping losses at higher rpm. Turbo diesel airflow is determined by load, with max flow at near top rpm.

Peter

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

I'm actually considering putting a K&N on my computer to keep the dust out. Right now I'm using some egg crate foam rubber. I think the K&N might actually work better in this application. Who knows I might just start a rice-nerd trend and I might be the first person to find an application K&N filters really are good for.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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