Community Forums

mikecosgrove · 09-11-2013, 03:20 AM

Ok guys and gals, this is my first post, I have been reading about all the fuss about gas mileage and the wisdom of driving slower to get better mileage, someone mentioned to me at the dealership that if I get a K&N airfilter it will improve my mpg. So tell me straight, have any of you used the filter and did it improve your mpg? I have a 2002 workhorse 8.1 with 26k miles and just doing a quick check after only 100 miles filled it up and figured about 6 mpg. Thoughts? Suggestions? Comments? Help?

Mike

Whatnobeer · 09-11-2013, 04:16 AM

Quote:

Originally Posted by mikecosgrove

Ok guys and gals, this is my first post, I have been reading about all the fuss about gas mileage and the wisdom of driving slower to get better mileage, someone mentioned to me at the dealership that if I get a K&N airfilter it will improve my mpg. So tell me straight, have any of you used the filter and did it improve your mpg? I have a 2002 workhorse 8.1 with 26k miles and just doing a quick check after only 100 miles filled it up and figured about 6 mpg. Thoughts? Suggestions? Comments? Help?

Mike

Hi Mike and

. I've used K&N on several cars including my old race cars and would swear by them. I'm not sure of real world with an engine that big but I know all the cars I've ever put them in I saw a slight to moderate HP increase and the same with MPG. I know these are cars and not big block RV's but it's a start. I think your 100 mile sample size is way to small. You need to run at least a full tank of fuel doing regular driving with your coach and probably a little more to get a true read on how well it works. Just my couple of lincolns worth. Good luck in the reasearch and welcome again.

Mystery · 09-11-2013, 04:28 AM

Welcome to the forum. Lots of great people and advice given through many years of hands on experience. K&N intake should also be balanced by a good aftermarket exhaust. Read up on Banks Performance. I have a diesel pusher and most folks do not advocate K&N for the diesel bc it let's in too much dirt. I am not sure of the effect on the 8.1. Many of the posts I have read seem to advocate intake and exhaust mods on the gas engine units. You may also want to research steering stabilizer and sway bars front and rear. I put a bully dog intake and mbrp exhaust on a ford f250 truck and immediately noticed a gain in mpg and power. Remember you are driving a house down the road and slow and steady will give you the best mileage in most cases. Give yourself plenty of braking distance too bc cars will cut in and then put on brakes and expect you and me to stop as fast as they can. Best Wishes to you and your family! Safe Travels!

JohnBoyToo · 09-11-2013, 04:29 AM

Welcome...two

there are 'differing opinions' on the benefits of any oil based filter...

Some say it let's too much oil and 'dust' thru the filter media that can cause issue with turbo's, maf's, etc...

Some say the hp improvements are only at the upper regions of rpm's and very rarely used for normal' driving...

Some say the mpg improvements are negligible....
and some mfg's are using it to deny warranty claims (if that's a concern!)

good luck, do your due diligence and enjoy !

gatorcq · 09-11-2013, 05:06 AM

K&N now has a filter for diesel engines. It is a water washable filter. I have seen it installed on both CAT Cummins engines. The cost equates to 3 filter replacement. So would I use one, Yes based on the cost saving.

So investigate this filter ;
K&N 38-2006S filter $200

Wolfpack Fan · 09-11-2013, 05:16 AM

I've used K&N's in car and pickup for many years. Performance or mileage improvements aren't really noticeable by seat of pants feel. At least to me they're not. As far as others claiming they allow more dust through them. I don't see how that's possible given they're an oiled cotton filter media. I like that they're serviceable NOT disposable. Maybe they'll save money over the long haul with a little improvement in economy. They'll definately save money over the long haul versus the cost of replacing paper filters. As far as affecting the mass air flow sensor. The jury is out. I suppose they could depending how close the MAF is to the filter.

worleybyrd · 09-11-2013, 07:06 AM

welcome

Coma · 09-11-2013, 07:09 AM

Here is a comparison of air filters. Note where K&N is.

ISO 5011 Duramax Air Filter Test Report

Bug512 · 09-11-2013, 07:23 AM

Welcome Mike !

I also own a workhorse with a 8.1. My average is 7 MPG. Personally I think if a air filter would have increased gas milage that significantly the manufacturer would have installed it from the beginning.

I would stay with the air filter that the manufacture recommends and put money toward the other maintenance aspects like fuel filter, sparkplugs, wires, cleaning of mass airflow sensors, O2 sensors.

Best of luck to you on owning a RV !

John H... · 09-11-2013, 07:25 AM

Welcome to the forum...

Gocoffeer · 09-11-2013, 07:38 AM

MIke.. I use a K&N filter in my Bounder.... Did I get a nice boost in fuel economy....NOPE... but I did get a little....went from 7.1 to 7.8 MPG on the same drive. Is that due to the air filter... no idea. But I would like to think it was..... I have read the included report on paper versus oil and see that K&N did not do too well in the filtration test....will i run out and buy a paper filter..NOPE....the K&N will remain.

CampDaven · 09-11-2013, 07:46 AM

Quote:

Originally Posted by Coma

Here is a comparison of air filters. Note where K&N is.

ISO 5011 Duramax Air Filter Test Report

Great info! Thanks!

If a "filter" does not filter, is it a filter?
I prefer clean engine guts!

I have no questions about K&N.

wb7auk · 09-11-2013, 08:57 AM

As a point of interest when buying filters make sure you are not getting out of date
old stock.

wa8yxm · 09-11-2013, 12:31 PM

First K&N filtlers.. As others have said I have seen a few gigibytes of argument on how much "Grit" they let through.. I used one on my 1992 Lumina,, and I'm convinced it did improve power and MPG slightly.

But for even better improvement you need to go with the entire K&N Intake, this is a re-designed way to get air into the engine that is less restrictive (or the Banks or Ultra Power kit, all of which are much alike)

And of course the exhaust can also stand an upgrade. I mean we get the air in.. we need to get it out.

Will these pay for themselves? Don't know

Will more Grit get through the K&N (*or other) filter? Same answer, Don't know, remain less than convinced of the dangers.

I was pleased with the performance of the filter on my Lumina... but I'm not quite daring enough to pop one on my 8.1L motor home.