K&N Cold Air Intake on '08 Dodge 6.7 Cummins

[daveinaz]

I recently put a K&N cold air intake system on our 2008 Dodge 3500 with the 6.7 Cummins in it. Just puttering around the neighborhood, I didn't really notice much difference. But over the weekend, I went for a little trip (not pulling the 5er) and accelerated like I usually do on the entrance ramp to the freeway. Before I got to the end of the ramp, about 100 feet before I could get over into the lane, I glanced down and was surprised to see that I was already going just over 75 mph!


Then I pulled the 5er around up to 55 mph and it seemed to have improvement there as well.

I don't know if the system actually gives the extra 20.63 hp or 43.35 lbs of torque, but judging by the highly scientific "seat of my pants" method, it does seem to be an improvement.

It was a pretty simple install.

[Dsull]

Allowing a Diesel to breath adds better response, and increased power due there being more air for the diesel to combine with. Less restriction at the intake allows the turbo create boost more efficiently.

Additionally, adding an exhaust to a pre-DPF truck will help with EGT's and turbo spool. You don't have to straight pipe it, I run a 3" downpipe with a 4" exhaust with Magnaflow muffler, dropped my EGT's and got better response out of my turbo. Granted if you want loud, that doesn't hurt either.

I'd give you my thoughts on the post DPF trucks, but the EPA and all.

[daveinaz]

Originally Posted by Dsull

Allowing a Diesel to breath adds better response, and increased power due there being more air for the diesel to combine with. Less restriction at the intake allows the turbo create boost more efficiently.

Additionally, adding an exhaust to a pre-DPF truck will help with EGT's and turbo spool. You don't have to straight pipe it, I run a 3" downpipe with a 4" exhaust with Magnaflow muffler, dropped my EGT's and got better response out of my turbo. Granted if you want loud, that doesn't hurt either.

I'd give you my thoughts on the post DPF trucks, but the EPA and all.

yeah, delete kits were available to me but I didn't want to go illegal and worry about passing emissions every year.

BTW, did you mean post DEF trucks? Does your exhaust mod for the pre-DEF diesels do away with the emissions or would it still be undeleted?

[Montana Man]

Increased ariflow always helps. Probably not to the numbers advertised. Try installing a Banks tuner on it and it will feel like a new truck.

[mlh]

Did you ever wonder why Dodge, Cummins or for that matter no manufacturer uses a K&M filter or one like then on their vehicles if they will improve power and gas or fuel mileage? The reason is they do NOT filter as good as a manufacturer’s paper filter and will dust your engine. That is allow dust to bypass it and get in the cylinders and oil. You can prove it to your self by having an oil test ran or do a Google search.
Lynwood

[Dsull]

Def was introduced after DPF. DPF is Diesel Particulate filter. It's basically a giant catalytic converter that catches all the soot. It will regenerate at times which is it basically gets the catalyst hot and then sprays diesel fuel onto it to burn it out. I think dodge started putting them on at the 2007.5 year trucks. Increasing the diameter post DPF can help, but I don't think it would be as noticeable as full exhaust I don't have anyone I know that has done one.

DEF is a fluid that is sprayed into the exhaust stream to break down NOX emissions. It is introduced after the turbo but before the DPF. It was introduced on the dodge trucks I think in 2013. They were the last light duty line to start using DEF.

This is just very basic explanation. Theres a lot of crap that goes into these systems. If your truck is an 08 it should have a DPF. If you do a lot of city type low speed, stop and go, you'll want to take her out to stretch her legs every so often. we've had the best luck with regen on our work trucks running them down the freeway for about 45 minutes. Dodge is nice enough to not tell you if your in regen mode, but if you have a EGT gauge you'll see an increase of EGT's, or if you have an edge insight or the like I think they tell you as well.

Hope this helps.

[daveinaz]

Originally Posted by Dsull

Def was introduced after DPF. DPF is Diesel Particulate filter. It's basically a giant catalytic converter that catches all the soot. It will regenerate at times which is it basically gets the catalyst hot and then sprays diesel fuel onto it to burn it out. I think dodge started putting them on at the 2007.5 year trucks. Increasing the diameter post DPF can help, but I don't think it would be as noticeable as full exhaust I don't have anyone I know that has done one.

DEF is a fluid that is sprayed into the exhaust stream to break down NOX emissions. It is introduced after the turbo but before the DPF. It was introduced on the dodge trucks I think in 2013. They were the last light duty line to start using DEF.

This is just very basic explanation. Theres a lot of crap that goes into these systems. If your truck is an 08 it should have a DPF. If you do a lot of city type low speed, stop and go, you'll want to take her out to stretch her legs every so often. we've had the best luck with regen on our work trucks running them down the freeway for about 45 minutes. Dodge is nice enough to not tell you if your in regen mode, but if you have a EGT gauge you'll see an increase of EGT's, or if you have an edge insight or the like I think they tell you as well.

Hope this helps.

DOH. Yeah, I had a brain fart. I knew that the 08 had DPF and EGR. I was debating whether to get the 07 with the 5.9 Cummins without the EGR/DPF but finally decided that the exhaust brake and 6-spd tranny on the 08 was worth it.

[daveinaz]

Originally Posted by mlh

Did you ever wonder why Dodge, Cummins or for that matter no manufacturer uses a K&M filter or one like then on their vehicles if they will improve power and gas or fuel mileage? The reason is they do NOT filter as good as a manufacturer’s paper filter and will dust your engine. That is allow dust to bypass it and get in the cylinders and oil. You can prove it to your self by having an oil test ran or do a Google search.
Lynwood

I know it's a debated topic. And if this was a foam/oiled filter that K&N has on some applications I'd probably agree with you but it is not. It is a paper element filter.

As for why manufacturers don't put better equipment on their stuff, I think it's a cost factor and they are aiming for the supposed best thing to most people.

[Dsull]

Originally Posted by mlh

Did you ever wonder why Dodge, Cummins or for that matter no manufacturer uses a K&M filter or one like then on their vehicles if they will improve power and gas or fuel mileage? The reason is they do NOT filter as good as a manufacturer’s paper filter and will dust your engine. That is allow dust to bypass it and get in the cylinders and oil. You can prove it to your self by having an oil test ran or do a Google search.
Lynwood

Cost of manufacture and ease of maintenance, as well as quieter intake noise.

Moving from the benefit of an unrestricted intake to the filtration is a different discussion.

In general, a properly maintained aftermarket filter does not dust your engine. A K&N filter can cause problems if over oiled (MAF issues), or under-oiling (Dust in motor). It also depends on the area's you're driving in. I haven't used a K&N so I won't say one way or the other to my experience but I know guys making big ponies running oiled filters that haven't had issues and they've got some coin wrapped up in their motors. Most are running S&B filters. I'm also sure they keep them proper.

He's says he's running a dry filter so it shouldn't be an issue.

Also, if you're worried, you can run a UOA at each oil change and see if you have an increase. For reference sake, my intake is a Bills Custom and I run an AEM Dryflow filter. 200k since the change and no difference in my oil. I test every fluid at every oil change since I get it for free.

[Dsull]

Originally Posted by Montana Man

Increased ariflow always helps. Probably not to the numbers advertised. Try installing a Banks tuner on it and it will feel like a new truck.

Banks, or spring for EFI Live custom tuning. 2008 is I think the first year that it became available on the Cummins. I know on my Duramax it is amazing, and can change on the fly like the 6-gun, or Juice.

[mlh]

I didn’t know K&N made a paper filter. I have never saw a scientific test where any aftermarket filter did a better job or as good of filtering air than an OEM filter.
Lynwood

[daveinaz]

Originally Posted by mlh

I didn’t know K&N made a paper filter. I have never saw a scientific test where any aftermarket filter did a better job or as good of filtering air than an OEM filter.
Lynwood

Here's the system:
https://www.knfilters.com/cold-air-i...-intake-system

K&N (supposedly) has dyno tests (they send a copy with the kit) that show the increase in hp and torque. I guess I'm taking their word for it -- however, they also have a money-back guarantee -- if you dyno your truck stock, then dyno it with the kit installed, if it doesn't show an increase, you can send the kit back and they'll refund you.

Also, they say that it's not just the filter making the difference but also the smoother air flow of the different intake. Less turbulence or something.

Beats me. I got the system still in the box when I bought the truck and figured I might as well install it. Like I said, maybe it's all in my mind, but it seems better.

Not wanting to start a debate, just posting my experience with it.

[mlh]

Dave thank you for posting this. I always like to learn things. I have always ask why.
Lynwood

Dave after looking at your web page I think you have a standard washable K&N air filter. Do a google search to find out how effective it is as compared to an OEM. Sure it will flow more air but at what cost. There are many good scientific tests that compare air filters.

[Dsull]

Originally Posted by mlh

Dave thank you for posting this. I always like to learn things. I have always ask why.
Lynwood

Dave after looking at your web page I think you have a standard washable K&N air filter. Do a google search to find out how effective it is as compared to an OEM. Sure it will flow more air but at what cost. There are many good scientific tests that compare air filters.

The intake increasing power and response is dependent on the restrictions in the stock system. The filtration is a good question, but as long as your not seeing an increase in silicon in your oil, or if you live were I live Iron to a lesser extent the benefit is worth the change.

I do recommend doing a UOA on your truck at least once a year, it'll tell you a lot about the health of your engine, there's many companies that do it, and it's only around 30-50 bucks.

[mlh]

I agree, if you have a Diesel engine you should get your oil tested. It will tell you a lot about your truck engine. Things there is no other way to find out. I had 13% fuel in my oil before a DPF delete.
Lynwood
https://nicoclub.com/archives/kn-vs-oem-filter.html
Here is a good scientific test.

[oddjobal]

I have had a K&N filter on my 5.9 Cummins for years. The first thing it did is improve overall performance. The second is fuel mileage. I went up 1-1 1/2 MPG. Plus the fact that 2 standard filters are about the same price as 1 K&N. Smart thing to do.

[Bad Moon]

I had a K&N system on my previous (gasser) Truck, and will never have one again. You could run your finger in the inlet duct after the filter and feel the grit. Also, the oil gets on the MAF sensor and you get a check engine light. Diesels work differently than gassers. The factory air filter on my Duramax provides more than enough airflow for the horsepower and torque I am making, and beyond, and filters better than the aftermarket units. Your money is better spent elsewhere.

[steiny93]

Originally Posted by daveinaz

I recently put a K&N cold air intake system on our 2008 Dodge 3500 with the 6.7 Cummins in it. Just puttering around the neighborhood, I didn't really notice much difference. But over the weekend, I went for a little trip (not pulling the 5er) and accelerated like I usually do on the entrance ramp to the freeway. Before I got to the end of the ramp, about 100 feet before I could get over into the lane, I glanced down and was surprised to see that I was already going just over 75 mph!


Then I pulled the 5er around up to 55 mph and it seemed to have improvement there as well.

I don't know if the system actually gives the extra 20.63 hp or 43.35 lbs of torque, but judging by the highly scientific "seat of my pants" method, it does seem to be an improvement.

It was a pretty simple install.

We run cummins farm trucks.

But we build for longevity, we have an '08 that was powerup'd to 1200lbs when it had 100miles on the odo, its at 250k now and 75% of those miles are towing, the lightest empty trailer it pulls is about 7k. Typical load for us is in the 30-50k gross range to as high as 100k.

On your vintage of Ram, deleting EGR / DPF and dropping in a tuner will get you crazy positive results; then based on your EGT's you can start thinking about getting more air through the system (intake / exhaust). You only need to worry about exhaust / intake if you have too high of EGT's or you aren't getting the power you need, if those are both in check you can leave them alone (intake / exhaust can really ruin drivability).

If you go the tune route go with a system that lets you monitor EGT's and trans temp. You want to have it auto defuel for either of those conditions.

I just switched from pulling my 5th with an HDT to a Ram Mega with the cummins; I haven't done a single power add to the Ram because the drivability is so high and it "just works". With the relatively light weight of the Montana, its been a joy to not have the loud pickup vs the farm setups .

[mlh]

Originally Posted by Bad Moon

I had a K&N system on my previous (gasser) Truck, and will never have one again. You could run your finger in the inlet duct after the filter and feel the grit. Also, the oil gets on the MAF sensor and you get a check engine light. Diesels work differently than gassers. The factory air filter on my Duramax provides more than enough airflow for the horsepower and torque I am making, and beyond, and filters better than the aftermarket units. Your money is better spent elsewhere.

People listen to the K&M hype. They are fine for a race engine when it will be rebuilt or replaced after the race but for your RV truck the OEM filter is a much better choice. It will protect your engine, which the K&M will not do and provide more than enough air. The factroy spends tons of money to develop the factory filters use them.
Lynwood

[JABURKHOLDER]

Have a K&N air filter on my 85 Mustang GT purchased new in ‘85. Been used as a daily driver and drag racing. Still have the Mustang and it still has a K&N filter.

Had a K&N air filter on my ‘06 F250 diesel for 10 years.

Have a K&N air filter on my ‘16 F350 diesel.

Never an issue on any of these vehicles. Once a year I clean and re-oil the filter.

The filter material is gauze, not paper like someone previously posted.