I haven't had a chance to take an in-depth look at anything yet but the "slapping" has turned to "ticking" now at every start up & does not really go away. It is present only between 750-1,000 RPMs. Above 1k, no ticking & below 750 no ticking.
Loud engine ticking from 03 Wrangler X 4.0
- Thread starter JABCAT
- Start date
From what I can hear, which is always different in a video, it still sounds like a bottom end noise. Very curious what you eventually find.
What I find most interesting, is that these engines seem to be able to *sometimes* go hundreds of thousands of miles with broken piston skirts. I guess it all depends on where and how much of the piston cracked. Of course sometimes the engines just blow up, and that's why this problem is so annoying.
What I find most interesting, is that these engines seem to be able to *sometimes* go hundreds of thousands of miles with broken piston skirts. I guess it all depends on where and how much of the piston cracked. Of course sometimes the engines just blow up, and that's why this problem is so annoying.
We purchased the Jeep 1/28/2023 & it had 154,800 mi on it. 2-owner Jeep, 1st owner had it over 18 years, all maintenance records & it looks like it was towed behind an RV most of it's life. Great condition over all. 2nd owner had recent maintenance records as well even having all the fluids changed the weekend before we looked at it. Engine was quiet, no issues I could spot.
In the just over 2 years we've owned it we put just 2k mi on it. Worked on refreshing all the suspension a few months ago & noticed an exhaust leak. Confirmed by a well-respected off-road shop. Ordered a set of shorty headers & sure enough found the original exhaust manifolds to be cracked in multiple locations.
That's when all the slapping & ticking started. So I'm a little frustrated, but also aware things happen on a 22-year-old vehicle with 158k mi. I appreciate all the help & suggestions from the forum.
Your milage is again nailing down most likely piston noise. My XJ started making the noise 2 years ago, at 159,000 miles, and I went down the deep, deep rabbit hole on this. It's still clanking away in there after another 11,000 miles, hasn't changed much. I'm inclined to just see what it does and deal with it if and when the engine disintegrates. The only flaw in this strategy is that I no longer trust it for long road trips. That's OK, I have other cars for long road trips, but it's still annoying.
Every I6 motor made by Chrysler, from '95-06, had the new design pistons, and they pretty much *ALL* start to crack at almost exactly the 160,000 mile mark. And now all these post '95 Jeeps are starting to get to that milage, and the complaints are starting.
Plenty of people go past160,000 miles with no noise, but when the engine is eventually torn down, almost all of the pistons have cracks in them, even if they were otherwise noiseless. Sometimes the cracks are small or in places where it doesn't lead to noise, but the cracks are there.
If the crack leads to a big chunk of piston skirt coming off, then the noise is loud. Little chunks, maybe no noise. As this becomes more generally well known, people are going to be a lot less willing to pay the huge money for TJs, and especially the insane money post '95 XJs are bringing now. Because a lot of expectation is that these engines will still do 300-400,000 miles without issues. They don't. Most people do not realize that yet.
Because the pre-'95 engines did 400,000 miles all the time. I think we are going to see a huge price drop in XJs when the general Jeep buying population finally realizes that the post-95 engines start falling apart past 160k miles.
And an even bigger problem now is that there is no good engine builder remanufacturing these engines any more, because the a lot of the parts are Chinese, and they just dissolve in a few thousand miles. Jasper used to be the goto for a good rebuilt motor, now their engines are just junk, not just because of poor remanufacturing technique (by all accounts Jasper doesn't put them back together like they used to), but mostly because the camshafts and lifters and other parts they are sourcing from China disintegrate, sometimes in just a few hundred miles.
I think there is a HUGE opportunity here for someone to start a good Jeep 4.0 engine remanufacturing business, building bulletproof 4.0s in the old way, out of ZERO CHINESE PARTS, because ballpark figure: close to one million of these engines are starting to break their pistons now, all these cars are just getting over 150,000 miles. Huge demand beginning. Most people don't want to spend the time, and also do not have the skill, to do an in-frame piston swap and would probably rather just have a great rebuilt engine swapped in, that really will do 400,000 miles. Or just junk it, which is so sad. Probably TJs will be junked a lot less often, but XJs.... well they're kind of pieces of junk lol.
The other big issue with these engines now, is that something that changed in the oil, probably less Zinc/Phosphorus from EPA regulations... the camshaft bearings are wearing out prematurely and leading to these motors having low oil pressure. And changing out camshaft bearings in these engines is very difficult, and nearly impossible without pulling the engine and letting an experienced shop do it.
ETA: the post-'95 4cylinder motors do the exact same thing too, just not sure what milage the disintegration starts at.
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I'm so excited to try this, I hope it restores my pistons by sucking the chunks of skirt out of the oil pan and gluing them back onto the bottom of the pistons where they belong.
Unfortunately, no. Some other projects, like replacing 100 linear feet of fence & getting a new a/c system for the house have taken priority. I think it's burning oil, but tbh I'm having a difficult time reading the level on the dipstick. It's very loud/fast ticking at start up then slows way down once warmed up & no ticking above 2k rpms.
Thanks - have watched those as well as other videos re: the possible fixes. My issue is finding time (or someone) to properly diagnose & fix it.
I don't think you are wrong but I don't think you are right.
There were a lot of companies remanufacturing/rebuilding the I6 and that number is dwindling to the few we have left. The one that are left are reputable companies using non USA made parts because there aren't any USA parts available. Lots of machine shops have closed over the last decade. Quality mechanics have become scarce and are better known as parts changers today.
Here is the issue as I see it. A new engine is going to cost (assume) 4 grand and install of 2 grand on a vehicle in typical shape selling for 6 grand. Most people are going to opt to sell it to the scrap yard for $300 worth of steel or $1,000 to the mechanic that broke the bad news to the customer. These are 20 year old machines and there is no true collectors market for them which would encourage a rebuild. And certainly all of those other vehicles with the 4.0 aren't worth buying spray paint to cover the rust.
Parts. I do not know for sure that there aren't any USA internal parts made anymore but I am willing to bet there are none. My justification for this is simple, if there aren't any USA made sensors there won't be any internals.
Marketing. Is a daunting task to inform the million drivers thT you have the best rebuild on the market and they will all buy yours. USA parts cost more and your rebuild will cost more in parts and labor. Not saying it is not worth it but many times people choose the least expensive route.
If I come to the point of needing to replace my 4.0 I will get online, find the phone number for Dexter's brother and order one from him. Then I would drive there and while making the road trip I would turn it into a vacation to a beautiful part of the country.
Could someone make a good living doing this? Yes, certainly. Is there a huge opportunity, I do not believe so.
I'm in a similar boat as the OP. In prepping for parts ordering I started listing what I was going to need and what I might need/want. Why not replace the oil pump and timing chain set if I've got the engine torn down that much?
I took some things apart today to first check for an exhaust leak before diving into anything more complex. Ran the engine without the catalytic converters connected - no real noticeable ticking. Replaced the exhaust manifold to catalytic converter bolts and j-nuts. Started it back up and loud ticking. I think I've pinpointed it to this catalytic converter. You can clearly see exhaust escaping from the top of the converter (not the header/converter joint.
* I edit my thoughts above. When I put everything back together & started it up large plumes of smoke came out the tailpipe. I don't have any free time coming up so need to find a shop to properly diagnose & repair.
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