Project Dodge Mega Cab: K&N Diesel Performance

Oct. 05, 2010 By Jaime Hernandez

Now that we have our KORE Performance Suspension System in place, we are finding that the truck is begging for more power. We decided it was time to start working on the diesel performance.

The factory settings on the Turbo Diesel Cummins are very conservative to help keep your truck running through its 100k mile warranty. The engine can do so much more.

We wanted to increase our MPG, horsepower and torque on our Dodge Cummins without going crazy.  One of the easiest ways to do this is by upgrading the factory air filter with an aftermarket one. We looked at a few different options on the market ranging from dry to oiled media filters. In the end, we choose the K&N Filter from K&N Engineering ( because of its technology, performance and million-mile warranty.


K&N 57 Series FIPK (Part# 57-1532) ( for Dodge 5.9l 24v Cummins Turbo Diesel, 2003-2007

We have used K&N Filters over the years on other 4x4 gas engines, dirt bikes and quads—all with great experiences. They all showed an increase in power and reliability, even in dusty off-road conditions. We expect nothing less from K&N’s diesel lineup.

We had two options, a factory air filter replacement or a complete system that would replace the restricted factory air box and ducting. Both work well and will increase power, but if you really want to uncork your Cummins, the higher HP and torque gain are with the K&N 57 Series Generation II intake, (a.k.a. K&N FIPK).

The K&N 57 Series FIPK replaces your air box and restricted air ducting feeding the Holset turbo with a smooth flowing system.  According to K&N, their 57 Series FIPK system showed a gain of 10.96 HP and 20.17lbft Torque @ 2852 RPM on the 5.9l 24v Cummins Turbo Diesel.  Not bad for a bolt on that can be done in under 1 hr.

Dynometer test results provided by K&N Engineering for stock 3rd Gen. Dodge 2500 w/ 5.9l 24v Turbo Diesel Cummins.
Tools needed for the job are:

• Flat screwdriver
• 5mm allen wrench
• 2.5mm allen wrench
• Ratchet
• 9/32” socket
• 10mm socket
• 10mm wrench
• 13mm wrench
• 14mm wrench
• 15mm wrench

Step-by-step instructions are provided by K&N, which makes it a breeze when putting the system together. There are a series of brackets, nuts, bolts, intake tube, hose clamps and two K&N Filters. For our purpose, we will just give an overview.

First thing you want to do is disconnect your batteries (2 on the Dodge Turbo Diesel). Then proceed to remove your Air Temperature Sensor.

Since you have the air temperature sensor out, it’s not a bad idea to do some maintenance by cleaning it out. We use MAF & Temp Sensor cleaner from CRC.

Carefully remove the hose clamps on the factory intake tube attached to the air box and turbo.

Next, carefully remove your air box. There are some rubber grommets you will need to wiggle the base of the box out from.

Once you have the factory air intake system out, it’s time to bolt on brackets for your K&N FIPK Diesel Intake System. There are a total of two brackets that will be holding the heat shield in place. One of the things you will need to do before you completely fasten things down is to bolt on the air temperature sensor to the K&N heat shield.

The air temperature sensor gets its own little K&N filter.

K&N provides a new silicone hose to connect the intake tube to the Holset turbo.

There’s a separate bracket that bolts on to the alternator, which helps support the intake tube. Once that’s in place, you can proceed to slip the tube into the turbo. Use the supplied hose clamps to tighten and get a good seal on the turbo inlet. 

Once your K&N intake tube is secured, you can add the big K&N diesel air filter. The large filter already came pre-oiled, so we just had to oil the little guy.

Make sure all the hardware, brackets and clamps are secure. Re-attach your batteries and start your engine.Check for any leaks or loose connections. If everything looks good, get ready to have some fun with your new K&N FIPK Diesel Intake System.

The K&N FIPK for the 5.9l 24v Cummins is a great bolt-on upgrade. It took less than one hour to do the job, and the benefits thus far have been amazing. Right after finishing our installation, we took a 900-mile trip up into the Sierra Nevada Mountains. We drove from San Diego, through the Mojave Desert, and up to an elevation of 9,000 ft with a fully loaded truck. It did awesome!

The turbo has gained some audibility, and we love it. With the increased airflow the turbo also seems to spool faster, improving boost. The throttle response, horsepower and torque has definitely improved—it’s most noticeable when passing and going up hills. 

Before we added the K&N, we were averaging 21 MPG on the highway. On our 900-mile trip to the Sierras, which included driving in town and off-road, we actually gained 1-2 MPG cruising at 65 MPH.

K&N’s Million Mile Warranty and CARB-approved sticker for the K&N FIPK II System.

The best part is that the K&N FIPK Diesel Intake System is C.A.R.B.-approved, and comes with an exemption sticker. So no sweating bullets when diesel smog time comes.

So far, we’re equally impressed with K&N’s diesel line as we have been for years with their gas motor products.

We’ll be honest, we weren’t sure about using an oil media filter on our diesel at first, but after getting some questions answered by K&N, we feel we made the right choice.

We had the opportunity to interview Lucio Tapia from K&N Engineering on some of the diesel engine air filtration issues and myths floating out there. Lucio, are dry media filters better than oiled K&N filters?

K&N Engineering: Dry media filters and oiled K&N filters have different characteristics. One of the biggest differences is that the K&N air filters are designed to last a lifetime and use oil as a tacking agent on the cotton to allow the media to be less restrictive while having excellent filtration. Some dry media filters are not re-usable and need to be replaced once they are clogged. One of the biggest differences between a dry filter and an oiled filter is the way they are maintained. Usually, a K&N filter will outflow a dry media filter due to the cotton media being less restrictive.
In our opinion we hit the sweet spot – an optimal blend of high air flow, filtration efficiency, durability and dust capacity. K&N Air Filter media has been tested both in-house and by independent labs using the ISO5011 test developed by the Society of Automotive Engineers. In addition we test many of our filters both in and out of the OE airbox ensuring proper fit and function. Our goal is to design filters with the maximum possible airflow achievable while providing guaranteed engine protection.
A lot more info on our website Does the oil in the K&N filters hurt diesel engines?

K&N Filters: No, it is both impossible and ridiculous.

It is impossible because we know that the oil treatment on our cotton is very small (usually less than 2 ounces). Once the oil is properly and evenly absorbed through the cotton, no oil will come off, even under extreme engine conditions. It is ridiculous, because no dealership or service provider has ever been able to provide us with evidence to support this "myth," and in fact, our investigations have revealed that even authorized dealerships are simply speculating and do not have the test equipment necessary to know whether the sensor has failed or why.

It is even more ridiculous because some car manufacturers use and sell air filters treated with oil on a regular basis. There are also major brands of disposable air filters that are treated with oil. We all use oil for the same reason, it helps in the filtration efficiency of an air filter. 
For more information on this topic including videos, see our Mass Air Flow Sensor Statement page Are K&N Filters legal in all 50 states?

K&N Filters: All stock replacement filters are 50 state legal. We offer many intake systems that are 50 state legal (all current diesel applications that we have are 50 state legal). The best way to determine the status of the part number is to look up the intake system for a specific application in our catalog or even better on our website (always up to date). Thanks, Lucio.

K&N Engineering, Inc.
1455 Citrus St.
Riverside, California 92507
(800) 858-3333 Newsletter
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