Fram air filter for TJ-poor mpg

About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
I used the stock champion plugs. It has about 45k on it. Oh yeah, it
is a 5-speed, 6cyl, all stock, etc.

No problem with the plugs. It was the air filter.

I bought a fram, which I usually wouldn't do, but...

The air filter had a 3/8" block of black foam glued on the bottom of
it. I've replaced the filter before, and never seen this.

My mileage instantly went from about 17mpg down to 14.5mpg. this went
on for 3 tanks of gas. My tire press. was ok.

the only thing I could think of was that strange piece of foam loosely
glued on. So I took that piece off. To say the least, it was barely
glued on.

And my mileage went right back to 17.

So when did they start gluing blocks of foam to their air filters?
And why, especially if it's going to kill your mileage. It's the same
dimensions, pleating and all, as a stock filter.

matt

The OE air filter also has that same type of foam glued to it. I doubt
it was the foam itself.

matt wrote:
> About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
> I used the stock champion plugs. It has about 45k on it. Oh yeah, it
> is a 5-speed, 6cyl, all stock, etc.
>
> No problem with the plugs. It was the air filter.
>
> I bought a fram, which I usually wouldn't do, but...
>
> The air filter had a 3/8" block of black foam glued on the bottom of
> it. I've replaced the filter before, and never seen this.
>
> My mileage instantly went from about 17mpg down to 14.5mpg. this went
> on for 3 tanks of gas. My tire press. was ok.
>
> the only thing I could think of was that strange piece of foam loosely
> glued on. So I took that piece off. To say the least, it was barely
> glued on.
>
> And my mileage went right back to 17.
>
> So when did they start gluing blocks of foam to their air filters?
> And why, especially if it's going to kill your mileage. It's the same
> dimensions, pleating and all, as a stock filter.
>
> matt
>

--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/

LOL!

Aha!

Something has ben bugging me about the new Jeep's crappy mileage....

Some folks say they can get 17 to 20+ mpg which is getting a bit close
to what the old 258 carb engine gives me and what my Cherokee 4.0 gives,
23+ mpg and others say they only get 13 - 14 mpg....

Could it just be the air filters? I don't use foam covered filters.

I think that would sure be worth looking into!

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Jerry Bransford wrote:
>
> The OE air filter also has that same type of foam glued to it. I doubt
> it was the foam itself.
>
> matt wrote:
> > About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
> > I used the stock champion plugs. It has about 45k on it. Oh yeah, it
> > is a 5-speed, 6cyl, all stock, etc.
> >
> > No problem with the plugs. It was the air filter.
> >
> > I bought a fram, which I usually wouldn't do, but...
> >
> > The air filter had a 3/8" block of black foam glued on the bottom of
> > it. I've replaced the filter before, and never seen this.
> >
> > My mileage instantly went from about 17mpg down to 14.5mpg. this went
> > on for 3 tanks of gas. My tire press. was ok.
> >
> > the only thing I could think of was that strange piece of foam loosely
> > glued on. So I took that piece off. To say the least, it was barely
> > glued on.
> >
> > And my mileage went right back to 17.
> >
> > So when did they start gluing blocks of foam to their air filters?
> > And why, especially if it's going to kill your mileage. It's the same
> > dimensions, pleating and all, as a stock filter.
> >
> > matt
> >
>
> --
> Jerry Bransford
> PP-ASEL N6TAY
> See the Geezer Jeep at
> http://members.cox.net/jerrypb/

On 1 Feb 2005 07:47:59 -0800, "matt" > wrote:

>About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
>I used the stock champion plugs. It has about 45k on it. Oh yeah, it
>is a 5-speed, 6cyl, all stock, etc.
>
>No problem with the plugs. It was the air filter.
>
What is the best air filter for the 4.0 Wrangler?

Joe Carroll
2K-TJ

There are some simple truths...And the dogs know what they are."
Joseph Duemer

Nearly anything paper and nearly anything but K&N. AC-Delco's paper
element air filters are very good.

Jerry

Joe Carroll wrote:
> On 1 Feb 2005 07:47:59 -0800, "matt" > wrote:
>
>
>>About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
>>I used the stock champion plugs. It has about 45k on it. Oh yeah, it
>>is a 5-speed, 6cyl, all stock, etc.
>>
>>No problem with the plugs. It was the air filter.
>>
>
> What is the best air filter for the 4.0 Wrangler?
>
> Joe Carroll
> 2K-TJ
>
> There are some simple truths...And the dogs know what they are."
> Joseph Duemer

--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/

What's wrong with K & N? I used one on a Stealth Twin Turbo for 3 years
and seemed to get better mileage with it, so put one in my TJ too and
haven't had problems. Does your recommendation apply to both the tube
add-on and the regular box air filters?
Thanks in advance.

Matt

On the other hand, when I changed the iar filter in my (new to me) `96
Cherokee I found that the previous owner either seldom changed it or liked
to leave it running outside a laundromat's vent. The element was
completely gray and caked in dust. Changing it out for a new Fram made
not one bit of diffrence in my gas mileage, though.



On Tue, 1 Feb 2005, Mike Romain wrote:

> LOL!
>
> Aha!
>
> Something has ben bugging me about the new Jeep's crappy mileage....
>
> Some folks say they can get 17 to 20+ mpg which is getting a bit close
> to what the old 258 carb engine gives me and what my Cherokee 4.0 gives,
> 23+ mpg and others say they only get 13 - 14 mpg....
>
> Could it just be the air filters? I don't use foam covered filters.
>
> I think that would sure be worth looking into!
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> Jerry Bransford wrote:
>>
>> The OE air filter also has that same type of foam glued to it. I doubt
>> it was the foam itself.
>>
>> matt wrote:
>>> About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
>>> I used the stock champion plugs. It has about 45k on it. Oh yeah, it
>>> is a 5-speed, 6cyl, all stock, etc.
>>>
>>> No problem with the plugs. It was the air filter.
>>>
>>> I bought a fram, which I usually wouldn't do, but...
>>>
>>> The air filter had a 3/8" block of black foam glued on the bottom of
>>> it. I've replaced the filter before, and never seen this.
>>>
>>> My mileage instantly went from about 17mpg down to 14.5mpg. this went
>>> on for 3 tanks of gas. My tire press. was ok.
>>>
>>> the only thing I could think of was that strange piece of foam loosely
>>> glued on. So I took that piece off. To say the least, it was barely
>>> glued on.
>>>
>>> And my mileage went right back to 17.
>>>
>>> So when did they start gluing blocks of foam to their air filters?
>>> And why, especially if it's going to kill your mileage. It's the same
>>> dimensions, pleating and all, as a stock filter.
>>>
>>> matt
>>>
>>
>> --
>> Jerry Bransford
>> PP-ASEL N6TAY
>> See the Geezer Jeep at
>> http://members.cox.net/jerrypb/
>

--
"I defer to your plainly more vivid memories of topless women with
whips....r"
R. H. Draney recalls AFU in the Good Old Days.

Simpleanswer --- a CLEAN one, and in light of the previous posts one
without a foam wrap. The LARGER (surface area) the filter the better
the engine efficiency and filter efficiency - reason: particulate in
air needs 'residence time' inside the filter media to become trapped;
the LARGER the surface the area the lower the velocity of air through
the filtration media and the higher chance that the particulate gets
trapped ON the surface of the filter instead of INSIDE the media. Once
debris starts to build up INSIDE the media, the service life and
efficiency (�P) quickly degrades. Think BIG, much bigger than what DC
provided !!!!!!!!!

Oil bath filters are ..... worthless unless you run exactly at the
precise rpm (volumetric flowrate of intake) specified for the filter.
The BEST removal with an oil bath is approx. 80% of particles and if
you dont run at the exact flow rate the removal efficiency degrades
drastically (both @ higher and lower rpm / flowrate CFM).

Obviously the foam wrap was detremental (in this case of the previous
discussion/posting) as it obviously increased the operating pressure
differential across the entire filter set - probably due to slopply
glueing and a semi-open-pore choice of foam. In most air filtration
applications the foam is detremental to pressure drop. The higher the
pressure drop the richer the resultant mixture. I take my hat off
to the poster who knew his engine intimately enough to know that
something was wrong (foam overlay) and simply removed it.

BTW - auto air filters (dry paper pleated types) vary all over the map
with respect to removal efficiency and differential operating pressure
..... even from the same 'manufacturer' and from lot to lot .... even
so, you usually get what you pay for. Just remember BIGGER is vastly
better.

(I'm deeply involved in filtration engineering and would NEVER not have
an air filter in place.)

Matt, My stock air filter (2001 TJ) had foam glued onto it also.
Replacements, OEM, didn't. Never could find out why it was dropped from OEM
filters - don't know if it added more filtration or robbed gas mileage. I
can get 19 MPG only on flat highways, 5th gear, no headwind. I do run 35"
tires so that's good. 17 MPG is normal for me.

Andy

"matt" > wrote in message
oups.com...
> About 2 weeks ago, I put new plugs and a new air filter in my 03 sport.
> I used the stock champion plugs. It has about 45k on it. Oh yeah, it
> is a 5-speed, 6cyl, all stock, etc.
>
> No problem with the plugs. It was the air filter.
>
> I bought a fram, which I usually wouldn't do, but...
>
> The air filter had a 3/8" block of black foam glued on the bottom of
> it. I've replaced the filter before, and never seen this.
>
> My mileage instantly went from about 17mpg down to 14.5mpg. this went
> on for 3 tanks of gas. My tire press. was ok.
>
> the only thing I could think of was that strange piece of foam loosely
> glued on. So I took that piece off. To say the least, it was barely
> glued on.
>
> And my mileage went right back to 17.
>
> So when did they start gluing blocks of foam to their air filters?
> And why, especially if it's going to kill your mileage. It's the same
> dimensions, pleating and all, as a stock filter.
>
> matt
>

matt wrote:
> About 2 weeks ago, I put new plugs and a new air filter in my 03
sport.
> I used the stock champion plugs. It has about 45k on it. Oh yeah, it
> is a 5-speed, 6cyl, all stock, etc.
>
> No problem with the plugs. It was the air filter.
>
> I bought a fram, which I usually wouldn't do, but...
>
> The air filter had a 3/8" block of black foam glued on the bottom of
> it. I've replaced the filter before, and never seen this.
>
> My mileage instantly went from about 17mpg down to 14.5mpg. this
went
> on for 3 tanks of gas. My tire press. was ok.
>
> the only thing I could think of was that strange piece of foam
loosely
> glued on. So I took that piece off. To say the least, it was barely
> glued on.
>
> And my mileage went right back to 17.
>
> So when did they start gluing blocks of foam to their air filters?
> And why, especially if it's going to kill your mileage. It's the
same
> dimensions, pleating and all, as a stock filter.
>
> matt


Matt,
I use CarQuest filters (which are WIX) and haven't had any
problems.
Sometimes those air boxes are tricky to seal back together and will
cause loss of MPG for some reason. It happen to me not too long ago.
You might check the duck work coming to the air box for junk. I know
around here squirrels will deposit nuts for the winter most anyplace
in an engine compartment.
Tom T