It is time to change the air filter, TJ 2001, Auto, 6 Cyl, 4L, Export, RWD. Rockauto offers WIX or Denso for $6-8 and a Mopar air filter for $23. Does it matter which one?
Thank you for your help.
Thank you for your help.
Does it matter which air filter I use?
- Thread starter Phuket
- Start date
AC-Delco has pulled the #1 spot in a few tests but I'd also run a Wix, Denso, Purolator, Fram, or a Mopar without hesitation.
Just say no to K&N.
Just say no to K&N.
Thank youAC-Delco has pulled the #1 spot in a few tests but I'd also run a Wix, Denso, Purolator, Fram, or a Mopar without hesitation.
Just say no to K&N.
Fram made changes to their 4.0 filter a few years ago and it no longer seals in the air box. Unless they've revert back.
Why is the K&N not good to use. I've used them on several vehicles including 3 TJ's and never noticed any problem. Jerry, could you comment on this?
xxdabroxx
TJ Addict
I bought 3 of them a couple years ago and they had the same foam seals I remember them having. I have two of them left and they seal fine.
16-17 years ago before I knew any better I installed a K&N air filter (for a reason explained below) that a wheeling buddy noticed. He suggested I pull it off and wipe my finger around inside the air tube and inside of the throttle body. I was absolutely shocked/stunned how much gritty dirt there was inside that had gotten past the K&N.
It freaked me out so bad that I installed not one but two pre-filters over the top of the K&N which mostly stopped the problem. I couldn't go back to the stock air filter and air intake box because I had installed a belt-driven York compressor that made it impossible to keep the factory air intake in place. This photo shows those two pre-filters pulled back, a K&N Outerwears and a foam Unifilter, so they can be seen. I first installed K&N's Outerwears but its fit was so sloppy that dusty air got around it. I added the Unifilter to hold the Outerwears against the K&N so the dusty air couldn't get around it.
This is why I couldn't go back to the factory air intake which I wished I could have...
So far as the K&N air filters go, various lab-conducted filter tests show its abysmal ability to actually filter dirt & dust out of the air. This is just one of the charts in one ISO-5011 lab test that pretty well sums up just how shitty of an air filter the K&N is. Read at the very last sentence below, the one that is bolded and underlined. They are the lab's words, not mine. ISO stands for International Standards Organization which means the tests were conducted to precise lab standards.
Last edited:
I just took a look at my receipt. I bought some in 2016 that didn't fit they changed the construction between those and the filters I bought previously. Maybe they changed them back?
MountaineerTom
LJ Enthusiast, Retired USAF Weapons Loader
Supporting Member
Ride of the Month Winner
I had a K&N cold air intake on my ‘99 Silverado at one time. I had taken the tube off a little while later for some other work and noticed the same accumulation of dust as Jerry mentioned. I removed it and went back to A/C Delco and Purolator Filters.
I’ve been using the same in my Jeep.
I’ve been using the same in my Jeep.
Just goes to show how much BS there is out there to help sell a product. I bought into the K&N myth years ago without doing any research. Sure sounds good but when you look at the hard lab data as in the ISO comparisons, K&N does not measure up to the sales pitch.
Similar threads
