Another newby to NAXJA and XJ's

poppa willie

NAXJA Forum User
I bought a 2wd 94 XJ for my daughter to drive as her first car back in August. Now I want one, only 4wd. I'm looking for a good daily driver to make some mods to. Have an eye on a 2000 XJ in the north AL area. Any others out there around the north AL area that you would pass along?
 
Welcome aboard!

Craigslist seems like the best way to find them around here. Also check the SEC classifieds section as there are always some rigs for sale there. Of course they are located all over the South.
 
Welcome to playground!!!!

IMHO the '99 would be a better year to get. They have a better intake and flow air better. The '00 and '01 could have a LP D30 and they also have had some issue with the heads cracking. Just my .02. I know you can only buy what you can find though. Good luck.

There are several on the forum here for sale too.
 
If the head has a casting number of 0331, that's the suspect head. They did it for emissions reasons I think. They get hot and then...crack.

Maybe someone else can chime in for the specific reason they changed...
 
They did it for emissions yes... the 0331 head has smaller exhaust ports than the 99 and older. This was done to increase the amount of heat in the engine and reduce emissions by making the converters hotter (which it also has 3, where as 99 and older only have one). The extra heat causes the head to crack... Also, the 00 has a coil on plug ignition system which isn't the very best as far as modability goes. The larger intake was installed to keep power up since the smaller head inherently hurt performance. However, jeep also installed the same intake on the 99's but they had the higher flowing head too, so out of any 4.0, the 99 had the most power from the factory. ONe more thing, like Mark mentioned, the 99 also has the better high pinion D30 front axle where as the 00-01 has a weaker low pinion design. I agree, look for a 97-99. If it has the "log style" intake, you can always swap over to the 99-01 style if you so choose.
 
Thanks Tyler. I thought that was why, I just didn't know all the details.
 
Personally I like the 98. It still has the higher flowing head. You can easily put the 99+ intanke on and get more power.

Edit: From the things I've read 99 was the year the heads changed and had smaller exhaust ports. That was the reason for the intake manifold change. The 0331 was just a thinner casting.
 
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Um, I don't think so, but im not 100% sure... I thought the 98 and 99 had the same head, I'm almost positive as a matter of fact. There wasn't a casting that was only used for one year (99).

Here's what I thought:
87-90: 2686
91-95: 7120
96-mid/late 99: 0630
later 99-04: 0331

I thought all of the 0331's had the coil on plug ignition, which the 99's don't have...
 
im not sure about the 99 head but i know the reason for the new intake was because of "detuning" the motor for the purpose of emmisions and mileage, they had to make up for the lost power somewhere.... i think th 0331's are just bad castings, they usually pop at 100k like clockwork
 
Tyler I think you're right. My '99 doesn't have the 0331 head nor the coil on plug ignition but it has lots of power.:yelclap:
 
Welcome! We can always use another Bama member....I'm on my second '01, and if there were no other issues, I'd grab a '99. But couldn't find what I was looking for both times.....AND I think the first '01 did have the head issue....mysterious loss of coolant....not sure the "new" one has it, yet....it pulled stronger than the first, but was substantially lighter when I got it. Now I've changed gearing, so hard to compare. I found my first on Autotrader in TN...and the second one on NAXJA in GA.
 
Just pulled this off Wiki:

1996-1999 4.0L (242 CID) I6 MPI (High Output) **Chrysler Block Cast** - 190 hp @ 4750 rpm, 235 ft lb @ 3,000 rpm

That doesn't make since. It should be more that 190 hp if it has the same head and the tuned intake.


Edit: In the middle of the 1999 model year, vehicles with the 4.0 liter (242 CID) engine received a much improved intake manifold. This was done to help counteract smaller exhaust porting on the latest casting of cylinder heads, which was done to meet more stringent emissions control laws.
 
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Just pulled this off Wiki:

1996-1999 4.0L (242 CID) I6 MPI (High Output) **Chrysler Block Cast** - 190 hp @ 4750 rpm, 235 ft lb @ 3,000 rpm

That doesn't make since. It should be more that 190 hp if it has the same head and the tuned intake.


Edit: In the middle of the 1999 model year, vehicles with the 4.0 liter (242 CID) engine received a much improved intake manifold. This was done to help counteract smaller exhaust porting on the latest casting of cylinder heads, which was done to meet more stringent emissions control laws.

They changed the heads in 99 for the 2000 model year.... got to remember that in 1999 they are already producing the 2000 model year....
 
Yeah, well, all I know is that all 0331 castings had the bungs cast for the coil pack bolts. Jarrad's and Mark's 99s both have the high flowing intake, but not the cast in bungs so they still must be 0630s... Does that seem logical???
 
So looks like sometime in '99 they went to the new intake before going to the new head. Then for the start of '00 models they went to the new head?
 
I did some more digging as well and it looks like they came in with the new head casting mid year or so in 99. I talked with the owner of the 2000 that I mentioned. He had to replace the motor 20,000 miles ago because it over heated. He found another 2000 motor to go back in. I've now found a 98 I'm going to look at this weekend. Thanks again for all the help! I'm excited about getting involved.
 
So looks like sometime in '99 they went to the new intake before going to the new head. Then for the start of '00 models they went to the new head?
Bingo ! (and to make it interesting, the wrangler and Grand started using the 0330 and coil packs at the beginning of 99)

and just to throw a wrench in the works the XJ at about the same time in mid 99 production, went from composite rotors to cast rotors and different hubs.
 
Do you know when in the production they went to the different rotors? What month?
 
Do you know when in the production they went to the different rotors? What month?
yes, it was January 1999, you can use either compostie or cast with either HP or LP D30 or the 2wd tube are all the same bolt mount setup, but you just have to match rotors to bearings.

heres an example: you could take the "rotor and hub" from a early 99 2wd and put it on a late 99 4wd, but you need to have both, hub and rotor, a late 99 rotor wont fit on a early 99 hub and vice versa
 
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