I could of swore i read in here somewhere that 99 xjs had a bad motor in them. If someone could fill me in that would be great cause i am about to by one, seeng how my 95 got washed away in a flood.
Seasoned Member
I thought '99's are a good year for XJ's. They got the improved intake and they were the last year for the 0630 cylinder head, although it seems to me that late '99's might have gotten the 0331 head and the new ignition system. If I was buying one, I'd look for the earlier although I'm not sure that the 0331 head is a deal breaker if everything else looks good.
tjwalker
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- Join DateNov 2010
- LocationIn the middle of Minnesota!
- Posts:5,840
- Year1999
- ModelCherokee
- Engine4.0
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Likes:156
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Liked:117 Times in 104 Posts
IMHO, 99 is probably the best year. Yes, I'm a little biased as I own one, but I've worked on all years and would buy another 99 or a 98 in a heartbeat.
While I have heard that there are a very rare few late 99's with the 0331 head, I've never actually seen confirmation of this and have asked in a couple of threads. However, all of the 00-01 4.0 engines have them.
Easy enough to find out though. Take a rag, wipe the area of the lip of the head about halfway back on the drivers side. With a light, you will be able to read the casting number on the head. The 99 should have the 0630 cylinder head, which is a very good head.
While I have heard that there are a very rare few late 99's with the 0331 head, I've never actually seen confirmation of this and have asked in a couple of threads. However, all of the 00-01 4.0 engines have them.
Easy enough to find out though. Take a rag, wipe the area of the lip of the head about halfway back on the drivers side. With a light, you will be able to read the casting number on the head. The 99 should have the 0630 cylinder head, which is a very good head.
Seasoned Member
Quote:
While I have heard that there are a very rare few late 99's with the 0331 head, I've never actually seen confirmation of this and have asked in a couple of threads. However, all of the 00-01 4.0 engines have them.
Easy enough to find out though. Take a rag, wipe the area of the lip of the head about halfway back on the drivers side. With a light, you will be able to read the casting number on the head. The 99 should have the 0630 cylinder head, which is a very good head.
+1. All the hate some people have on here for the '99 is actually based on misinformation that '99's all have the 0331 head.Originally Posted by tjwalker
IMHO, 99 is probably the best year. Yes, I'm a little biased as I own one, but I've worked on all years and would buy another 99 or a 98 in a hearbeat. While I have heard that there are a very rare few late 99's with the 0331 head, I've never actually seen confirmation of this and have asked in a couple of threads. However, all of the 00-01 4.0 engines have them.
Easy enough to find out though. Take a rag, wipe the area of the lip of the head about halfway back on the drivers side. With a light, you will be able to read the casting number on the head. The 99 should have the 0630 cylinder head, which is a very good head.
CF Veteran
ok, the upgraded intake on the 99 is irrelevant unless it's on an older model. The reason for the intake is because in 99 chrysler made changes to the exhaust and computer as well as a few other things to reduce emissions, that also reduced the power output by 15 horse. so they upgraded the intake to try to regain some of that power. so a 99 with a 99 intake = stock jeep without the option for an intake upgrade.
Most 99's do not have the 0331 head so that isn't usually a problem.
in 98 for some god unknown reason chrysler decided to use all the same sensors but change the plugs on all of them so the older ones won't fit, and they can charge you 2 to 4 times as much. Other than that, they're good though. Not much downfall to them.
Most 99's do not have the 0331 head so that isn't usually a problem.
in 98 for some god unknown reason chrysler decided to use all the same sensors but change the plugs on all of them so the older ones won't fit, and they can charge you 2 to 4 times as much. Other than that, they're good though. Not much downfall to them.
CF Veteran
I love my 99. It was built in june. Should I check the head to make sure?
My buddy has a 2k. I told hime he is ridding around in a granade...lol but so far so good.
My buddy has a 2k. I told hime he is ridding around in a granade...lol but so far so good.
CF Veteran
Quote:
What I said was not misinformation... lol, not bashing your 99, just stating some of the differences.Originally Posted by bigvig
I wouldnt want anything other than my '99. Like others have said, lots of misinformation.
Junior Member
Or just buy it and drive it until it fails. Its not guaranteed to fail if its the 0331. But if it does like my '00 did (at 195k!), you can make a frankenstein engine. I have a stock '00 block and intake with an 0630 head from a '99 and running coils. The only thing that I ran into is that nobody seems to stock the right upper heater hose. I guess placement changed slightly..?
CF Veteran
I'm running an early '99.
it had 254xxx miles on the original motor, trans, tcase, and clutch. minimal rust (for the salt belt), and the only thing wrong with it was the motor had a bad wrist pin.
I put a '95 mopar remanufactured block with .030 pistons in it with a '95 head, the '99 intake, borla, bored TB, srt4 injectors, etc.
it rips. the old motor is being bored and rebuilt as a stroker. and it had an 0630 head casting, not 0331. I'm still putting the spare '95 head that I have on it, as the exhaust ports are bigger, and it has a higher nickel content in the casting.
so, long way around, it's perfectly fine. I wouldn't want the distributorless setup...too much PITA to deal with.
it had 254xxx miles on the original motor, trans, tcase, and clutch. minimal rust (for the salt belt), and the only thing wrong with it was the motor had a bad wrist pin.
I put a '95 mopar remanufactured block with .030 pistons in it with a '95 head, the '99 intake, borla, bored TB, srt4 injectors, etc.
it rips. the old motor is being bored and rebuilt as a stroker. and it had an 0630 head casting, not 0331. I'm still putting the spare '95 head that I have on it, as the exhaust ports are bigger, and it has a higher nickel content in the casting.
so, long way around, it's perfectly fine. I wouldn't want the distributorless setup...too much PITA to deal with.



