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  #1  
Old July 4th, 2012, 06:17
LYKOS LYKOS is offline
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2001 Pre-Cat replace

I've searched and can't find any sort of write up on this.

When I change my pre-cats will I need to remove the intake or is it possible to do it without?
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  #2  
Old July 4th, 2012, 14:51
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Re: 2001 Pre-Cat replace

Well, I don't have a 2001 but you should be able to do so as long as you can get to the bolts. You'll need to drop the trans crossmember to get the assembly out.

Why do you need to change them?
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Old July 4th, 2012, 16:58
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Re: 2001 Pre-Cat replace

Just run an aftermarket manifold, or an earlier model without pre cats. In theory you can get away with untoling the manifold and lift up on it if you have room to do everything.
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  #4  
Old July 4th, 2012, 20:45
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Quote:
Originally Posted by Johnnie Walker View Post
Just run an aftermarket manifold, or an earlier model without pre cats. In theory you can get away with untoling the manifold and lift up on it if you have room to do everything.
Careful. The cat-nazis here will close this thread, beat your wife and steal your first born for making a statement like that.

No you don't have to remove the manifold. You also don't need to remove the crossmember. There is a junction right under the transmission. Unbolt it there and then where it bolts to the manifold. You should be golden..

Did you buy a set yet? I ordered some from Parts Train and I'm about to go ballistic on them. They keep giving me bad tracking numbers that don't show up on UPS's website and although they have charged my card it keeps showing pending and won't go through all the way. I ordered it last week.
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Old July 4th, 2012, 21:05
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Re: 2001 Pre-Cat replace

LOL, I thought it was the Cat-Gestapo? LOL
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  #6  
Old July 4th, 2012, 21:08
LYKOS LYKOS is offline
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I'm calling a local supplier who gets them from Walker. They're made 90 miles north of here.

Why??

Its time and there are other issues such as power loss and overheating that if nothing else will be helped by the replacement.

To me, at 141,000, its a maintenance item.
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  #7  
Old July 5th, 2012, 07:44
Talyn Talyn is offline
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Re: 2001 Pre-Cat replace

The precats are bolted to the manifold, not part of it. Some precats are welded to the exhaust pipe, some are bolted on. Magnaflow offers the weld in replacement, but not legal in Cali.
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  #8  
Old July 5th, 2012, 08:41
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Re: 2001 Pre-Cat replace

Quote:
Originally Posted by Talyn View Post
The precats are bolted to the manifold, not part of it. Some precats are welded to the exhaust pipe, some are bolted on.
Oddly, the FSM shows the "one piece" where the cats are welded to the downpipe. It states you need to remove the cross member.

Yet the parts guide shows the "two piece" where the precats bolt on.

I suppose you better look to make sure you get the right one.
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Old July 5th, 2012, 09:40
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Depending on which company you get your replacement from, they either require you to buy their extension pipe which bolts on the bottom of the pre cat unit and goes back to the regular cat or others are "direct" bolt in which don't require that piece.
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  #10  
Old July 5th, 2012, 09:52
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Re: 2001 Pre-Cat replace

Last time I had to replace a downpipe, I simply unbolted the passenger side of the crossmember and dropped it down with a jack until I could slide the exhaust out. YMMV.

Also - on a federal emissions (2 or 3 O2 sensors, I forget which) 00/01, there is almost no difference between the older style setup and the newer dual manifold setup except you'll have to do something to adapt the 0331 head to the older header. On the cali emissions (4 O2 sensor) ones you are going to open a can of worms by switching to the older style, since you'll have to customize stuff to put all those O2 sensors in without either setting off codes or having to add precats or something after the fact anyways. I'd probably just replace with a factory equivalent like the weld-in magnaflow ones mentioned... since you're in VA not CA I doubt they'll care at all.

This is why I just avoid 00/01 jeeps. Too much complicated crap added by then.
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  #11  
Old July 5th, 2012, 10:00
LYKOS LYKOS is offline
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Re: 2001 Pre-Cat replace

Yup yup!~!!

I'm keeping it legal and as simple as possible. Going with the factory style setup.


I love my Jeep, might have bought a 99 if I knew then what I know now...
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  #12  
Old July 5th, 2012, 10:02
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Re: 2001 Pre-Cat replace

Quote:
Originally Posted by LYKOS View Post
I love my Jeep, might have bought a 99 if I knew then what I know now...
Understatement of the century, Brotha!
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  #13  
Old July 5th, 2012, 10:03
LYKOS LYKOS is offline
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Re: 2001 Pre-Cat replace

Either
http://shop.advanceautoparts.com/web...GRPEXHAAMS____

Or
http://performance-curve.com/642311-...r-1-1-1-1.aspx


Unless I'm missing something they look identical and it all comes down to price.
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  #14  
Old July 5th, 2012, 15:07
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Re: 2001 Pre-Cat replace

Quote:
Originally Posted by DrMoab View Post
Careful. The cat-nazis here will close this thread, beat your wife and steal your first born for making a statement like that.

No you don't have to remove the manifold. You also don't need to remove the crossmember. There is a junction right under the transmission. Unbolt it there and then where it bolts to the manifold. You should be golden..

Did you buy a set yet? I ordered some from Parts Train and I'm about to go ballistic on them. They keep giving me bad tracking numbers that don't show up on UPS's website and although they have charged my card it keeps showing pending and won't go through all the way. I ordered it last week.
I understand why the pre-cats are there, but they are unnecessary really. In the Dakota's some of the later models had pre-cats, some did not. A common thing to do was swap in the non pre-cat manifolds, as long as the downstream cat is there it shouldn't matter. Other than CA wanting more money.
I was not saying to remove all cats, just the pre-cats, but it is what it is.
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  #15  
Old July 5th, 2012, 18:25
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Agreed but you still have to deal with the two extra o2 sensors.

It's easier just to put it back the way it was.
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