mattphillips90

I need to swap my exhaust manifold and was wondering, can any of the inline 6 engines use the same exhaust manifolds? It might be easier finding a newer TJ or Grand Cherokee with a good manifold than an XJ from 01 if I can even find one that new in the JY.

BotakBeng

Just wondering why are you replacing an old one.....
Search Vendor section, there is one that's selling for around $140.

Qroberts7

If there's nothing wrong with the one you have now don't waste time and money swapping. But if you do have a crack or something don't pull something from a jy cause then you'll probably be changing it again. Get something aftermarket that has the bellows in it so it can expand if needed.

mattphillips90

Mine has a crack and is ticking pretty bad. Dont really have the money for a nicer one right now and a jy one is only 20 bucks

K-SKI

correct me if im wrong but i have been told you can swap all year jeeps you just have to change the down pipe
ie: if u have a non ho you can swap i a ho header but you have to change the down pipe

Qroberts7

What year is your xj?

mattphillips90

Its a 98

Cherockee

I believe up to early '99 will work. Be sure to check the header for cracks before you purchase.... I haven't seen a used one that wasn't cracked and repaired yet.

Qroberts7

You can get a set of steel headers with the bellows for a 98 for about 140 shipped on eBay.

ZINGGG

http://www.ineedparts.com/index.php?...oduct_id=15343

Get it and don't look back. Also take a look at your motor mounts while you're in there. That's the #1 reason the manifold cracks

mattphillips90

What should I look for to make sure theyre alright? Ive looked them over once but didnt really know what to look for

RenegadeT

the factory manifolds all crack in the same place, I think its where the #3 or 4 tube meet the main runner. I've used a JY mainfold, because like you said, it was cheap, and the engine I yanked it from was already tore down. I race my XJs and it cracked soon, should've welded it up first.

Save yourself the headache of having to change downpipes, stick with XJ/YJ/TJ/MJ/ZJ 4.0L HO 91-99 maniolfds. The earlier manifolds are shorter, also have the oxygen sensor in the (different sensor than 91-99s). You would have to remove the O2 sensor from your downpipe, and put it into the new-to-you earlier manifold. You would aslo have to use the earlier downpipe, and I'm not sure if that downpipe would use the same flange near the tranny as your 98.

mattphillips90

What exactly do you meam HO motor. Not trying to be dumb but I cant figure it out haha. Also yea my manifolds cracked I found them and I had it welded up but it still ticks. I think it may be leaking at the flange because its dented in and I think its not sealing right so I may just need a new flange. Also how will I know if my motor mounts are bad? Thats what I was saying ive looked at but cant tell if theyre bad.

5-90

#1 - Cracked manifold = Check your Engine Mounts!

Reports from the field indicate that a cracked manifold is almost invariably preceded by engine mounts failing. They don't have to "chunk out" on you, but you'll note that they're really soft. If you're replacing one, replace all three (engine left/engine right/transmission tailcone.)

#2 - The big problem with the XJ exhaust system is that it's very rigid, and relative movement kills it. The best fix? Take your downpipe in to an exhaust shop, and ask them to replace a section of it with a flex joint. That's even better than the aftermarket manifold with the bellows in the #1 and #6 primaries (because it's not the #1 and #6 primaries alone that are the problem.) (NB: This is what I'll be doing as a part of the refit on my 88. I haven't had a cracked manifold yet, but I plan on redoing just about everything anyhow.) I think the later (2000-2001 w/#0331 head and precats) have a split downpipe with a short Wye section - have the flex joint welded into the straight single section instead. This also saves having to wrestle with branches, getting them to line up (since the OEM Wye section isn't disturbed.)

#3 - Exhaust manifold swapping:

1987-1990 w/#2686 head will swap freely amongst themselves. You may be able to swap outside of this range, but I haven't confirmed.

1991-1995 #w/7120 head - swap freely.

1996-1999 w/#0630 head - swap freely.

2000-2001 w/#0331 head - swap freely.

The #7120 manifold should replace the exhaust on the #0630 head, but this is a one-way swap - the primaries on the #0630 manifold are smaller (as are the ports in the head,) and the later manifold will not fully cover the earlier ports.

The #0331 manifold is a special case, and will only swap with itself (this is because it has the two "pre-cats" in it, and you'll get a persistent DTC if you eliminate them.

Chances of swapping between various models gets smaller - if you have a more specific question, feel free to ask (I haven't finished assimilating all of the data to hand yet.) However, information given is opinion based on Hollander Interchange (a source I have learned to consider "definitive") and reports from the field.

mattphillips90

Say whaaaaaa?

You sir are the man! THe flex idea is great, guess Ill replace my mounts and have a flex joint installed to see if possibly it is just my flange that is causing the leak and not my re-welded manifold.