The K&N filter issue has been covered many times, and in depth.

My 300SD... Aaron says its "destoyed" (chrome wheels)
http://www.peachparts.com/shopforum/mercedes-benz-wheels-tires/117835-my-300sd-aaron-says-its-destoyed-chrome-wheels-post840084.html#post840084

K&N Filter Efficiency Tests
K&N Filter Efficiency Tests

K&N for the OM603
http://www.peachparts.com/shopforum/diesel-discussion/104986-k-n-om603-post721322.html#post721322

K+N Filters - for a Diesel ??
http://www.peachparts.com/shopforum/diesel-discussion/103562-k-n-filters-diesel-post710523.html#post710523

Air Intake Mod....
http://www.peachparts.com/shopforum/diesel-discussion/63464-air-intake-mod-post984631.html?posted=1#post984631

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

In the words of Homer Simpson, "That's what I've been trying to TELL you!" Thanks for the valuable links. I knew I was correct in my assumptions.

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'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Yep waste of money for these cars at least.

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2016 Corvette Stingray 2LT
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Funny thing about most of the people on the Magnum forum that use the K&N filters, they don't plan on owning the car long time. Most are probably trading cars every 2 to 4 years and are not concerned about possible engine damage, it about the "sound" of proformance.

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'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

They're bad for any engine....they let it too much dirt.

If you use one, put a paper filter behind it and se how much dirt it catches that the K&N didn't.

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79 300SD - $50 out of pocket purchase
03 Dodge Ram 3500 CTD
2003 VW Jetta TDI

Yep, Just hold one up to the light...........See for yourself.

Lots of holes in the filter for dirt to come thru!!!!!!!!!!!!!!!!!!!

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Matt (SD,CA)

1984 300SD.. White/Chrome Bunts..Green

1997 2500 Dodge Ram 5.9 Cummins 12 Valve 36 PSI of Boost = 400+hp & 800+tQ .. ..Greenspeed

2004 Dodge Ram 2500 4x4 Quad Cab Cummins 5.9 H.O "596hp/1225tq" 6 spd. Man. Leather Heated seats/Loaded..Flame Red....GREENSPEED

Global warming...Doing my part, Smokin da hippies..

Fight the good fight!......

How about marine engines? 98% of medium sided (800-2400 hp) marine diesels have a oiled gauze filter. Not much dust on the ocean....
So they do have a place that is within standard long term use applications- but it is not on a everyday driver if you want what is best for the engine and you plan on keeping the car according to nearly all well informed individuals.

My sentiments exactly - which is why I would never buy a vehicle that is pimped - unless it was for parts.

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.