K&N parts matching Luber-Finer AF4031 air filter

The Luber-Finer AF4031 air filter cross references with the K&N air filter parts below. K&N offers compatible air filters for many Luber-Finer air filters giving you an alternative.
ProductPart NumberProduct Image 
K&N Replacement Air Filter
  • Designed to Increase Power
  • Million Mile Limited Warranty
DK, Portland, Oregon
Just now working on second tank of gas. Can't quite tell yet, but mileage seems to be just a little bit better with the new filter. I can definitely feel a difference in acceleration and overall engine output on my Tundra - it even seems to coast better with the improved air flow. Can't quite give it five stars because of the initial cost and the cost of the refurbish kits for when it's time to clean. Otherwise, I like it - makes you want to floor it just to hear the roar of the engine!
Tank, Roanoke, Virginia
I put K&Ns in all of my vehicles. Love the serviceability of the filter instead of just replacing the junk paper filter every 2 years. The only reason it didn't get 5 stars is the fact that I can hear a whistle coming from the air box now with the higher flow.
Thomas Grieve, Texas
Since I replaced the stock Toyota air filter with the K &N filter I've seen a slight difference in fuel mileage and horse power. Slight but noticeable.
33-2387 K&N 33-2387 Replacement Air Filter
List Price: $91.99
Your Price: $59.99