K&N's 33-2256 is a panel-style High-Flow filter for the 3.2L supercharged V6 in the Mercedes-Benz SLK32 AMG, model years 2001 to 2003, and two are needed per car. Its media is layered, oiled cotton with multiple layers of premium cotton gauze. Because it is washable, you can clean and re-oil it rather than buying a new disposable filter each service, and the manufacturer backs it with a No-Hassle Lifetime Limited Warranty. Owners on user forums say the change is most noticeable in intake sound and throttle feel, and mixed opinions exist about whether the power gain is measurable, so set expectations accordingly. Search terms: K&N 33-2256 SLK32 AMG filter, supercharged 3.2 V6 washable air filter, W170 SLK32 drop-in performance filter.
Stock paper elements are built for filtration first, while this filter is designed to seal firmly into the stock airbox with a urethane frame. Enthusiasts on user forums warn that over-oiling is the real risk: excess oil can contaminate the mass airflow sensor, so a light, even coat is the accepted approach. The filter is not a substitute for a cold-air system, and forum consensus is that the gain from a filter swap alone is modest.
The manufacturer lists this part as requiring two filters for the SLK32 V6 3.2L supercharged application, so order a pair.
The manufacturer specifies about 0.85 oz (25 ml) of re-oiling solution for this filter. Use a light, even coat, since owners on user forums link excess oil to contamination of the mass airflow sensor.
No. The manufacturer designs its replacement filters to seat in the stock airbox, so the factory housing is used as-is.
This is a straightforward job. The listed tools are a screwdriver, with an installation time of roughly 5-10 minutes per the manufacturer's product page. Remove the factory filter, wipe out debris from the housing, and drop in the new filter. Disconnecting the air intake tube from the air box lid can make it easier to maneuver the lid, and the manufacturer warns that if the filter, lid and base are not lined up correctly and you force the fasteners, you will most likely break the air box. Expect the clips to require slightly more pressure than a stock foam seal. Finally, the manufacturer recommends placing a K&N stop decal on the airbox so future technicians know the filter is washable.
