lfhoward

I am the proud owner of a 2000 Cherokee Sport, currently with 115K miles, and which I want to drive until it returns to the earth as iron oxide. It's the most fun AND practical vehicle I have ever owned.

Recently I've read a number of threads about the dreaded 0331 cracked cylinder head problem, such as this one by Spoonman: https://www.cherokeeforum.com/f2/99-...question-68242

On that thread tjwalker posted a link to an extremely informative discussion on Jeeps Unlimited about the issue, which affects wrangler 4.0's as well as XJ's built after late 1999 with the 0331 header. So, if you want info on symptoms, or at what mileage the bad header usually cracks, I highly recommend reading that thread: http://www.jeepsunlimited.com/forums...d.php?t=391831

I am pretty sure my XJ is fine at the moment-- no coolant in the oil or on the bottom of the oil filler cap, coolant level doesn't drop, and the oil pressure is fine at all rpms. But, probably like most '00 and '01 XJ owners, I am wondering about my chances that my header will crack in the future. The Jeep Unlimited thread had a poll of unlucky owners about what mileage the cracks appeared, but it couldn't shed any light on what percent of 0331 headers really do crack. When reading the post, it seemed like the problem was very common, but of course only folks whose headers cracked were likely to post and take the survey.

So here is our own CF survey for ANYONE who has a late '99 to '01 XJ with the 0331 cylinder head-- please answer the poll whether or not you have ever had the problem. To find out the actual percent of 0331 heads that cracked, everyone with an '00 and '01 XJ needs to take the survey, not just people who had the problem. Hopefully we can get a sense of how often the problem actually happens!

Also, please feel free to post solutions below. Did you replace your defective header with another remanufactured 0331 head, get a 1990's-era head and somehow attach your ignition coils, buy an aftermarket aluminum header, or what?

Cheers, and best wishes for 400,000 miles for you '00 and '01 XJ owners!
--LFH

MickDime

99 here @ 115k still going strong

irs009

I think a boogieman spreads rumors about this head...JK

TheJerm

I just picked up a 2000 XJ for my gf that has 202K on it. I know the head gasket was changed by the PO but i dont think the head was. It runs great

Rikkadog

A couple of things can cause cracked/warped heads. Overheating to the extreme is probably the most likely culpret. Incorrect torque or torque sequence will also do it, or the block being not flat withing tolerence. All of that should be checked if your head cracks.

aj6

ive looked in this injectors, cams, fuel delivery, pcms, ect. its all very different i dont know if it will even run the same.. to me this doesint seem like a good solution.. money wise too..

what ive been doing is full cooling sys maintenance every year. or 6 mos... the most heat is at the intake /exhaust ports.. ( most likely to crack ) makeing sher your cooling is runing at %150 WILL help fight with head cracking

TheJerm

I bolted a 01 intake to my 95, it runs great. You can put an older head on the 99+ but the big hurdle is the bosses for the coils. OR buy a revised 0331 head where the defect was fixed. Can be found on 02+ TJ's or bought new

aj6

a older truck with newer parts wood be fine to me.. but a 2001 truck with a 95 head doesnt.. you dont have to pass emissions i do..


they changed alot in the 4.0l over they years..

http://jeep4.0performance.4mg.com/tech_specs.html

TheJerm

Yea i dont have to pass emissions, i love MI. But i dont think using an older head on a 00 would affect the emissions much. You still would have the pre cats and main cat

BlackJ

OP- great poll. Sounds like if you stay on top of your cooling system the chances are you'll be ok.

cherokeeaddiction23

yep as long as your cooling system is in top condition then your fine, ive even had mine overheat completely and that was about 3 years ago, still to this day never had a problem with it

Shiro Elex

I've got 191k on my 2000, and I've never had a problem. A few weeks ago, I SEVERELY overheated it in Chicago's miserable traffic. It was my fault; left the radiator cap off. I pulled off to a gas station, topped off with some 50/50, and it's still doing great to this day.

tjwalker

Not all 0331 heads will crack, but many do.

If you own an 00-01, be **** about your cooling system maintenance. Radiator, water pump, thermostat, radiator cap, hoses (often overlooked), serpentine belt.

Many of these crack after an overheat.

cherokeeaddiction23

i defeinitely am, i flush it about twice a year just because lol, once before winter and once before summer

JGCORNEL

176,283 miles and still fine.