Airbox

gixxerkid3

YJ Enthusiast
Joined
Oct 4, 2021
Messages
135
Location
Washington
Question. What’s the difference between a OEM 2.5l and a 4.0l Airbox on a 1992 YJ? Looking at a really nice used OEM one on eBay for $99.99. Going to offer less though. Is there a difference size / attachment wise?

I currently have an aftermarket “KN” that the PO had on and I don’t like it.

604E5FC8-EC1A-4B97-AFF0-71D00AC6C258.jpeg
 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
Question. What’s the difference between a OEM 2.5l and a 4.0l Airbox on a 1992 YJ? Looking at a really nice used OEM one on eBay for $99.99. Going to offer less though. Is there a difference size / attachment wise?

I currently have an aftermarket “KN” that the PO had on and I don’t like it.

View attachment 119713
From 91-95 I believe they are the same airbox (they take the same filter) and just have different hoses to reach the throttle body on the engine. You'll have to confirm that but I think that's how Jeep did it.
 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
Ok, so worst case scenario I end up buying new hoses from O’reilly or something. Thanks .
By hose I’m talking about the big corrugated one going from the end of the box to the throttle body. Probably need to snag that off eBay if what you’re looking at doesn’t come with it or if it’s for the wrong engine.
 
OP
G

gixxerkid3

YJ Enthusiast
Joined
Oct 4, 2021
Messages
135
Location
Washington
Oh. Well this one comes with that . I was talking about the rubber vent hose. I should be good then. Do you think there’s any real benefit going back to stock from that stupid one I have on there now
 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
According to this parts diagram the big hose is different from 4.0 to 2.5. So make sure whatever you are buying has the big hose for a 2.5. The box and lid are the same. The hoses going from the box to the intake manifold, valve cover, etc should still be able to be bought or either engine I'm pretty sure.

On a 2.5 you have an elbow at the rear of the valve cover and a hose connects that to the airbox. At the front of the valve cover is a threaded tube with a hose on it. That hose goes to the intake manifold. So I don't think that front hose would be disturbed. You would need the hose to connect the rear valve cover elbow to your new air box. And then would need the hose going from the airbox down to the charcoal canister if you do not still have that.

Personally I hate aftermarket intakes, so I would say going back to stock is worth it. Not everyone would agree with me though.

1647889730445.png
 
OP
G

gixxerkid3

YJ Enthusiast
Joined
Oct 4, 2021
Messages
135
Location
Washington
Well. I was not aware that I would also need parts 13-16 as well . That changes the whole plan. The below is what I am looking at but if I need parts 13-16. I may pass.

 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
Well. I was not aware that I would also need parts 13-16 as well . That changes the whole plan. The below is what I am looking at but if I need parts 13-16. I may pass.

Mine does not have 13/15/16 from the factory. I have the little inlet piece that clips into the grille and slide into the airbox. I believe there is a little cab on the downward facing pipe. Probably what you have too.
 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
If I remember when i get home I'll take one. It's quite simple. I may be able to find a representation off the web in the mean time.
 

machoheadgames

Certified YJ Researcher
Supporting Member
Joined
May 19, 2020
Messages
1,312
Location
Dallas, TX
This is exactly what I have. Left part clips into the grille and sucks cool air from the front. that little protruberance is capped like the pic. The right end sticks into the airbox (the airbox slides onto it really) and then the airbox sits down on the fender bracket once it's on the tube far enough. Then you use the 3 clips to lock the box down to the fender bracket. Then put in the filter, set on the lid, hook all the hoses to the lid, and clip the lid down to the box.

you probably still have the part pictured below.


1647890561796.png
 
OP
G

gixxerkid3

YJ Enthusiast
Joined
Oct 4, 2021
Messages
135
Location
Washington
This is exactly what I have. Left part clips into the grille and sucks cool air from the front. that little protruberance is capped like the pic. The right end sticks into the airbox (the airbox slides onto it really) and then the airbox sits down on the fender bracket once it's on the tube far enough. Then you use the 3 clips to lock the box down to the fender bracket. Then put in the filter, set on the lid, hook all the hoses to the lid, and clip the lid down to the box.

you probably still have the part pictured below.


View attachment 119715
Lol. I just saw this very picture on eBay. Well the price is adding up if I need that. Not sure going back to stock is worth $140+
 

JKP

New Member
Joined
Feb 20, 2021
Messages
23
Location
Warner Robins GA
Actually you could buy the ebay box and then make something that slides in to replace the other part. The way it is designed with the turn down and being low in the grill makes it subject to sucking up water.
 

JKP

New Member
Joined
Feb 20, 2021
Messages
23
Location
Warner Robins GA
Better filtration is the main one, also, the box is less likely to suck in water splashed in the engine bay or thrown by the fan.

In dusty environments, the K&N lets too much dirt through and it's not improving perf as the factory filter does not restrict the 6 cyl much less the 4.