The K&N RU-3270 is a round, straight universal clamp-on air filter built on K&N's cotton gauze media, which the manufacturer designs for a wide range of uses including racing vehicles, generators, snowmobiles, and tractors. It has a 6-inch flange inside diameter, a 1-inch flange, a 7.5-inch outside diameter, and a 10-inch height. The manufacturer says the design is meant to increase horsepower and acceleration. Unlike a disposable paper element, this filter is washable and reusable, so the cost is a periodic cleaning and re-oiling instead of a new filter every service interval. Its rubber flange is molded to absorb vibration and can be stretched slightly to fit between standard sizes, which helps when an intake pipe is not an exact match. Searches for a 6 inch flange universal air filter, RU-3270 round straight intake filter, or washable cotton gauze clamp-on filter will land on this part.
The manufacturer does not list specific vehicle applications for this filter, so it suits custom intakes, off-road builds, and equipment swaps where the intake tube is already sized to a 6-inch flange. Measure the flange inside diameter, flange length, and the space available for the 7.5-inch body and 10-inch height before ordering. Owners on user forums who fit larger K&N universal filters often report that clearance around frame members, fenders, or the carburetor takes some patient repositioning, so check that area before committing to a cut or relocation. Per the manufacturer's install guidance for other K&N clamp-on filters, you should wipe out the housing, seat the filter fully, tighten the clamp, and confirm the seal before closing the lid.
Yes. The manufacturer states that K&N universal air filters are washable and reusable, and it lists a re-oiling amount of 2.67 oz (79 ml) for this model.
No. The manufacturer describes it as a universal clamp-on filter for a wide variety of applications rather than a vehicle-specific part, so the buyer must confirm that the intake's flange and body dimensions match the filter.
According to the manufacturer, the molded rubber flange can be stretched up to 1/16 of an inch (1.5 mm) to fit between standard sizes.
The manufacturer lists a one-year limited warranty on this filter.
Installation is a basic bolt-in or clamp-in job on most setups, but it is only as easy as the intake fitment allows. Start by removing the stock filter and wiping out any dirt in the housing. Slide the RU-3270 flange onto the intake tube or adapter, seat it fully, and tighten the hose clamp to create a seal. Owners on user forums who run K&N filters in factory airboxes commonly report that the filter can shift when the lid closes, so reposition it until the lid closes without forcing it. The manufacturer's install sheets for other K&N universal clamp-on filters also recommend that the seal be rechecked every time the filter is serviced.
