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2000 - 2001 Cali Emission Pre-Cat Converter ??

Redsnake

NAXJA Forum User
Location
Tulsa, OK
So I've been needing to replace my '01 XJ pre-cat converters for a while now and I'm ready to finally bite the bullet and get this done.

I've already ordered a new header f/ Rugged Ridge and now I'm trying to get the best buy I can on the pre-catalytic converters.

As far as brands go... Catco seems to have the best reviews and cost $240 +/- ... Walker & Davico and a few other 'cheaper' brands have hit and miss reviews. In looking on Rockauto's website I see Walker parts going for $179 and $403 ... not sure what the difference is?? Any suggestions on best places to get the Catco or other brands you've used would be greatly appreciated.

I know the 00-01 XJs w/ Cali emissions are not in the majority so there isn't a TON of online reference material to go thru. There are a couple decent write-ups I've found but no step-by-step so to speak. This past weekend I did a spark plug change on my XJ and got under my rig to get an idea of what type of job this might be. I can't see how you can get a wrench on the lower bolts to get the exhaust header off... it's such a TIGHT weave of exhaust pieces on my '01. I've swapped headers on a few earlier model XJ's and that's not a tough job... but I'm wondering how I can do this while leaving the engine in my rig. I'm thinking I may have to remove my front driveshaft and few other parts before I can even get that dang pre-cat off and swapped out. :\
 
Changing the mini-cats is a real PIA.
I did a valve job on my 01 a few years ago., adding a Banks header in the process.
After screwing with the manifolds unsuccessfully, I gave up and removed the head again.
After clamping the head to the bench, it was easy to bolt up the intake and exhaust, including the mini-cats.
I use a engine hoist to pickup the assembly for installation.
This seems like the hard way to do it but, in my XJ's case, it saved many hours of frustration of trying to access the hidden bolts. YMMV
 
You can disconnect the front driveshaft at the differential and tie it over towards the lower control arm. For the bolts, go at it from the bottom. A 15mm universal socket and 18" or 24" extension is the best way I found. The 15mm universal socket is a combination of a 15mm socket and universal adapter but is shorter than putting a socket on a universal. I am not sure about who makes the best catalytic converter. The difference in price is usually whether or not it CARB certified. CARB certification is needed for California and maybe one or two other Northeastern states. The warranties on the CARB certified parts may be better.
 
Thanks for the input! My biggest concern is that the Cat pipe fits just like OE... O2 Sensor locations are the same and welds/mounting locations are quality so it won't rust or leak. Price is secondarily a concern. I'd hate to pay $400 if the $200 part is basically the same specs. It doesn't have to be pretty, just function for me. :)
 
Followup:

This weekend I finally tackled this job of replacing my Pre-Cats on my '01 XJ. In the process I also replaced the OE Cast Iron manifold w/a copy of the Banks Torque Tube headers... the Rugged Ridge version for the '00-'01 XJs.

Let me just say WHAT A PAIN IN THE ... Arms... ;) I have in the past replace the cracked manifold on my '96 XJ and while the lower 2 bolts are a pain to access they are a piece of cake compared to the '00-'01 XJs w/the pre-cat design.

A few areas that were the hardest to handle.

* The 3 bolts (tri design) where the Pre-Cat pipe bolts to the downstream exhaust where rust welded to the OE pipe that I wasn't replacing. I busted all 3 nuts off, then had to cut off the remaining bolt and bolt head. Then I punched and drilled out those three bolts (this took me a couple hours due to the area and trying to get my hands and drill in the proper placement and whatnot) I had to run by Azone and pick up a few new 5/16" x 2" x 24 thread bolts, nuts and washers for install.

* When removing the OE Pre-Cat from the OE manifold I got 3 of the 4 bolts to actually back out and were in reusable condition, however the last bolt was again rust-welded to it's capture nut and I broke it when removing. Had I been able to re-use these it would've made installation easier. 1 of the bolts supplied w/the Rugged Ridge Headers (they provide 4 new bolts, washers and nuts for the Pre-Cat to Header install) was too long to fit. When tightening that bolt it would've hit the header pipe so it needed to be ~ 1/2" shorter and Rugged Ridge should've known this had they EVER tried to install one of their headers. I had to rummage thru my collection of old bolts/nuts and found one that fit. :\

* The RR Header flange is thicker than the OE Iron Manifolds so when bolting the Header and Intake up to the engine it wasn't a tight fit. I had to make some 'spacers' out of old washers that I cut in half or pieces of some Aluminum bar cut to 1/4" x 1" and use those as spacers. I was only able to do this to the Top bolts. It appears from looking that the bottom bolts snugged up both the Intake and Header. Another failure on RR's part. Perhaps the Wranglers have a different Intake design and they fit better but this one is said to fit '00-'01 XJs as well so it should fit better.

* Those bottom 2 bolts that we've all struggled with getting tight on XJ Header replacement jobs. I ended up removing my Motor Mount, Motor to Frame Mount (to get more room/access) Front Driveshaft and Wheel/Tire to get better access from below. In order to get those 2 bolts tight I used an open end / ratcheting wrench 14mm. It took a lot of patience and time but I finally was able to get those tight. :)

Of note:

The Rugged Ridge Headers where PACKED in what appears to be cosmolene grease... so it took a while to clean most of that off prior to install. It will stink and burn off for a while after initial startup and heat cycles. The supplied Header Gasket seemed to be of good quality and I used it for the install.

I used the Walker 52304 Pre-Cat which I ordered f/ RockAuto and should be getting a $50 rebate soon. This part was off good quality. Fit seemed to be good and welding and such was fine. This part goes unseen so as long as it works I'm good.

I replaced the Upstream O2 Sensors w/new NTK O2s. I had replaced the Downstream O2s ~ 6 months back so those were in like-new condition. So I should be good to go on that front for a while.

I've only driven my XJ for ~ 20 miles after the install but so far it's running smoother and seems to be a bit quieter... if that makes any sense. Can't really tell if there's any HP gain as I haven't really taken the RPM's much past 3K... and I'm guessing the RR Torque Tubes breath better the higher the RPM's get. Not sure what my mileage will be now. No Check Engine lights on yet post install. I had a P0432 code on my XJ for the past 2+ years... so hopefully this will take care of that.

Here's a few pics I took... didn't document it all as my hands were dirty and it took me ~ 15 hours total to get this job done over the weekend by myself.











The trouble spot where I had to cut, drill and manipulate this pipe to get the old bolts out and new bolts in



Where I had to add spacers for the Intake Manifold





No spacer as this is just the Header (top center bolt)



I didn't take any pics of the Cat or Intake installed... I kinda forgot as I was in a rush to get this back together. Besides, you all know what it looks like as all the 'good stuff' is hidden under the OE Intake. :)
 
Thanks for the write and pictures. Thinking I am going to be doing this soon in my CA Emissions '00. Still ruling out other possible culprits. Waiting for the CEL with the P0432 to come back after my most recent try. Been wondering how nuts I should go when push comes to shove and I do the cat. Was thinking about a header, kind of a waste on a stock 4.0, and was considering the RR. Not liking what you had to do though. Plus it always kind of bugs me that most of the headers, unless you pay big bucks, are one piece. I always kind of figured that Mopar went to the 2 piece design to help with the cracking problem that '99 and down seem to experience. But some people seem to think part of that problem is motor and tranny mounts not up to snuff. Really not looking forward to this.
 
The plus side is the collector is actually 2 separate parts... and that's where the cracks normally happen, at least in my experience. Good motor and transmission mounts and this header should be fine. At least I'm hoping it will be. My biggest 'complaint' would be that the thickness of the flange for the header is ~ 1/8"+ thicker than the OE Intake manifold and they both need to be very close to get a good seal as any Jeep owner knows. If I were to do it over again I'd notch the header flange w/a round grinder wheel until they were the same thickness as the Intake... then it'd be a non-issue.
 
Old thread but the 52304 is NOT california compliant. The 81850 is. Just curious what state you are in and if all your error codes and inspections went OK since installing the 52304?
 
Old thread but the 52304 is NOT california compliant. The 81850 is. Just curious what state you are in and if all your error codes and inspections went OK since installing the 52304?

There are 2 Walker front dual cat set ups for '00 and '01. The wording is as follows for the 52304:

For CA emission vehicles not registered in CA or NY.

I am in CT. Passes without a problem. Took care of my P0432 code. Also right after the install I cleared the computer like this:

https://www.cherokeeforum.com/f2/jeep-ecu-reset-procedure-46047/

After doing this all monitors were in an OK status in 26 miles. But I have learned that in my '00 I need to have at least 3/4's of a tank of gas for the Evap Monitor to come up quickly.

I replaced everything from the front dual cat back. With Walker parts.

I did not do this job. I deliver auto parts and am in pretty tight with some of the garages I deliver to. Have a garage I trust put the exhaust on for me. But since I wanted to do some housekeeping I hacked off everything from the dual cat so I clean up in there nice nice.

I was just unsure if I would be able to handle removing the front cat on the ground without air tools. I gave them everything they needed. Including new hardware I grabbed from my local Jeep Dealership, in tight with them too, for where the cat bolts to the exhaust manifolds.

Well they charged me $75 to remove the front cat, swap out the 2 O2 sensors, cause mine were almost brand new, and hang the exhaust. I was OK with that. LOL.

I guess I should have posted on this thread after. Sorry.
 
Changing the mini-cats is a real PIA.
I did a valve job on my 01 a few years ago., adding a Banks header in the process.
After screwing with the manifolds unsuccessfully, I gave up and removed the head again.
After clamping the head to the bench, it was easy to bolt up the intake and exhaust, including the mini-cats.
I use a engine hoist to pickup the assembly for installation.
This seems like the hard way to do it but, in my XJ's case, it saved many hours of frustration of trying to access the hidden bolts. YMMV

Sorry to bump this old thread but your pm’s are full.

Wanted to pick your brain a bit as I used one to pull them all as one and found it a bit tricky... thinking I won’t have as much luck trying to be more delicate getting it back in. Is there a certain angle or rotation that makes it easy? The drivers side motor mount and it’s heat shield seem to be in the way.
 
I'll shamelessly bump this as well. Is it necessary to remove to the intake manifold just to replace the precats?
 
I'll shamelessly bump this as well. Is it necessary to remove to the intake manifold just to replace the precats?

With the right extensions you can probably get them out from underneath
 
With the right extensions you can probably get them out from underneath

Thanks for the reply. I posted something similar in CF not specifically looking to see if you need to put something on both ends to loosen the bolt. The first one i got to seems to just spin which leads me to believe the spring clips evaporated or this was replaced prior to me getting it
 
With the right extensions you can probably get them out from underneath

Thanks for the reply. I posted something similar in CF more specifically looking to see if you need to put something on both ends to loosen the bolt. The first one i got to seems to just spin which leads me to believe the spring clips evaporated or this was replaced prior to me getting it
 
Thanks for the reply. I posted something similar in CF not specifically looking to see if you need to put something on both ends to loosen the bolt. The first one i got to seems to just spin which leads me to believe the spring clips evaporated or this was replaced prior to me getting it

Yeah that’s definitely not how it should be. It should rotate, hit the header and stop so you can loosen the bolt. May be easier to take the intake manifold off them so you have access to the top side.
 
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