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SKU: RU-5040 | UPC: 024844386199
K&N Universal Clamp-On Air Filter 3.5in Flg ID x 8.5x5.25in B OD x 6.25x4in T OD x 5.5in H
This K&.N RU-5040 oval tapered conical air filter delivers high-flow filtration for racing vehicles, radio-controlled cars, generators, snowmobiles, tractors, and off-road equipment. The 3.5-inch centered flange clamps securely to any compatible intake with pliable rubber that stretches up to 1/16 inch for precise fit. Washable and reusable cotton gauze media traps dirt while allowing maximum airflow for consistent power gains.
Key Features
- Oval Tapered Design: 8.5 x 5.25 inch base OD tapers to 6.25 x 4 inch top OD with 5.5 inch height for compact high-flow setups in tight engine bays
- 3.5 Inch Flange: 1.25 inch long centered rubber flange absorbs vibration, stretches 1.5mm for in-between sizes, ensures leak-free seal on intakes
- Cotton Gauze Media: Oiled four-layer filtration captures contaminants down to 1 micron while boosting airflow over paper filters
- Washable Construction: Clean with K&.N kit and reuse indefinitely without performance loss for long-term cost savings
- Versatile Application: Fits wide range of equipment from RC cars to industrial engines regardless of intake angle or offset
Product Notes
- Oil filter with provided K&.N oil for initial setup and maintenance
- Wash every 50,000 miles or annually with soap and water, re-oil before reinstall
- Ships in protective box, handle flanges carefully to avoid damage
Installation Notes
- Professional installation recommended.
- Clamp directly to 3.5 inch ID intake pipe, stretch flange if needed up to 1/16 inch
- Compatible with hose clamps or adapters, no special hardware required
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Any | Racing Vehicles | All |
| Universal | Any | Generators | All |
| Universal | Any | Snowmobiles | All |
| Universal | Any | Tractors | All |
| Universal | Any | R/C Cars | All |
| Universal | Any | Off-Road Equipment | All |
Why Choose K&.N?
- Proven leader in high-performance air filtration since 1969
- Engineered for durability with vibration-resistant rubber components
- Backed by extensive testing for reliable airflow in demanding conditions
Frequently Asked Questions
-
Q: Does this fit non-standard intake angles?
A: Yes, flexible flange design accommodates various angles and offsets on racing or custom setups -
Q: What material is used in the filter media?
A: Four-layer cotton gauze with proprietary red oil for superior dust holding and airflow -
Q: How do I maintain this filter?
A: Wash with K&.N cleaner, rinse, dry completely, apply filter oil evenly, reusable for life of equipment
Shipping & Handling
- Method: UPS Ground or FedEx
- Availability: In stock - ships same or next business day
- Packaging: Product box 9.06 x 6.81 x 6.5 inches
- Weight: 1.6 pounds
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